diff --git a/src/INSTALLpc.txt b/src/INSTALLpc.txt
index 3777784..071ede4 100644
--- a/src/INSTALLpc.txt
+++ b/src/INSTALLpc.txt
@@ -24,7 +24,7 @@
 5. Cross compiling for Win32 from a Linux machine
 6. Building with Python support
 7. Building with Python3 support
-8. Building with MzScheme support
+8. Building with MzScheme/Racket support
 9. Building with Lua support
 10. Building with Perl support
 11. Building with Ruby support
@@ -415,8 +415,10 @@
         PYTHON3=C:\Python34 DYNAMIC_PYTHON3=yes PYTHON3_VER=34
 
 
-8. Building with MzScheme support
-=================================
+8. Building with MzScheme/Racket support
+========================================
+
+1) Building with MzScheme support
 
 (written by Sergey Khorev <sergey.khorev@gmail.com>)
 
@@ -451,31 +453,75 @@
 %WINDOWS%\System32 only.
 
 
+2) Building with Racket support
+
+MzScheme and PLT Scheme names have been rebranded as Racket.  Vim with Racket
+(https://racket-lang.org/) support can be built with either MSVC or MinGW (or
+Cygwin).
+
+You need to set the following variables:
+
+    MZSCHEME:          Where Racket is installed.
+                       E.g. C:\Program Files (x86)\Racket
+    DYNAMIC_MZSCHEME:  Whether dynamic linking is used. Usually, set to yes.
+    MZSCHEME_VER:      Racket DLL version. E.g. 3m_9z0ds0 for Racket 6.3.
+    MZSCHEME_COLLECTS: (Optional) Path of the collects directory used at
+                       runtime. Default: $(MZSCHEME)\collects
+                       User can override this with the PLTCOLLECTS environment
+                       variable.
+
+E.g. When using MSVC (as one line):
+
+    nmake -f Make_mvc.mak
+        MZSCHEME="C:\Program Files (x86)\Racket" DYNAMIC_MZSCHEME=yes
+        MZSCHEME_VER=3m_9z0ds0
+
+Or when using MinGW (as one line):
+
+    mingw32-make -f Make_ming.mak
+        MZSCHEME='C:/Program\ Files\ (x86)/Racket' DYNAMIC_MZSCHEME=yes
+        MZSCHEME_VER=3m_9z0ds0
+
+    Spaces should be escaped with '\'.
+
+
 9. Building with Lua support
 ============================
 
-Vim with Lua support can be built with either MSVC or MinGW (or Cygwin).
-You can use binaries from LuaBinaries.
-    http://luabinaries.sourceforge.net/
+Vim with Lua support can be built with either MSVC or MinGW (or maybe Cygwin).
+You can use binaries from LuaBinaries: http://luabinaries.sourceforge.net/
+This also applies to when you get a Vim executable and don't build yourself,
+do the part up to "Build".
 
 1) Download and install LuaBinaries
+
 Go to the Download page of LuaBinaries:
-    http://luabinaries.sourceforge.net/download.html
+  http://luabinaries.sourceforge.net/download.html
 
 Download lua-X.Y.Z_Win32_dllw4_lib.zip for x86 or
-lua-X.Y.Z_Win64_dllw4_lib.zip for x64.  You can use them for both MSVC and
+lua-X.Y.Z_Win64_dllw4_lib.zip for x64.  You can use them both for MSVC and
 MinGW.
 
 Unpack it to a working directory. E.g. C:\projects\lua53.
 Lua's header files will be installed under the include directory.
 
+Copy luaXY.dll to your Windows system directory. The system directory depends
+on your Windows bitness and Vim bitness:
+  32-bit Vim on 32-bit Windows: C:\Windows\System32
+  32-bit Vim on 64-bit Windows: C:\Windows\SysWOW64
+  64-bit Vim on 64-bit Windows: C:\Windows\System32
+
+Or another option is copying luaXY.dll to the directory where gvim.exe
+(or vim.exe) is.
+
 
 2) Build
-You need to set the following variables:
 
-    LUA:         Where Lua is installed. E.g. C:\projects\lua53.
-    DYNAMIC_LUA: Whether dynamic linking is used. Usually, set to yes.
-    LUA_VER:     Lua version. E.g. 53 for Lua 5.3.X.
+You need to set LUA, DYNAMIC_LUA and LUA_VER.
+
+  LUA: Where Lua's header files are installed. E.g. C:\projects\lua53.
+  DYNAMIC_LUA: Whether dynamic linking is used. Set to yes.
+  LUA_VER: Lua version. E.g. 53 for Lua 5.3.X.
 
 E.g. When using MSVC (as one line):
 
@@ -487,7 +533,8 @@
     mingw32-make -f Make_mingw.mak
         LUA=C:\projects\lua53 DYNAMIC_LUA=yes LUA_VER=53
 
-Or when using Cygwin (as one line):
+
+Or when using Cygwin (as one line) (untested):
 
     make -f Make_cyg.mak
         LUA=/cygdrive/c/projects/lua53 DYNAMIC_LUA=yes LUA_VER=53
diff --git a/src/Make_cyg_ming.mak b/src/Make_cyg_ming.mak
index d89ba29..79628a8 100644
--- a/src/Make_cyg_ming.mak
+++ b/src/Make_cyg_ming.mak
@@ -171,26 +171,37 @@
 MZSCHEME_VER=205_000
 endif
 
-ifndef MZSCHEME_PRECISE_GC
-MZSCHEME_PRECISE_GC=no
-endif
-
 # for version 4.x we need to generate byte-code for Scheme base
 ifndef MZSCHEME_GENERATE_BASE
 MZSCHEME_GENERATE_BASE=no
 endif
 
-ifndef MZSCHEME_USE_RACKET
+ifneq ($(wildcard $(MZSCHEME)/lib/msvc/libmzsch$(MZSCHEME_VER).lib),)
 MZSCHEME_MAIN_LIB=mzsch
 else
 MZSCHEME_MAIN_LIB=racket
 endif
 
+ifndef MZSCHEME_PRECISE_GC
+MZSCHEME_PRECISE_GC=no
+ifneq ($(wildcard $(MZSCHEME)\lib\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll),)
+ifeq ($(wildcard $(MZSCHEME)\lib\libmzgc$(MZSCHEME_VER).dll),)
+MZSCHEME_PRECISE_GC=yes
+endif
+else
+ifneq ($(wildcard $(MZSCHEME)\lib\msvc\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib),)
+ifeq ($(wildcard $(MZSCHEME)\lib\msvc\libmzgc$(MZSCHEME_VER).lib),)
+MZSCHEME_PRECISE_GC=yes
+endif
+endif
+endif
+endif
+
 ifeq (no,$(DYNAMIC_MZSCHEME))
 ifeq (yes,$(MZSCHEME_PRECISE_GC))
 MZSCHEME_LIB=-l$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER)
 else
-MZSCHEME_LIB = -l$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER) -lmzgc$(MZSCHEME_VER)
+MZSCHEME_LIB=-l$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER) -lmzgc$(MZSCHEME_VER)
 endif
 # the modern MinGW can dynamically link to dlls directly.
 # point MZSCHEME_DLLS to where you put libmzschXXXXXXX.dll and libgcXXXXXXX.dll
@@ -429,10 +440,21 @@
 endif
 
 ifdef MZSCHEME
-CFLAGS += -I$(MZSCHEME)/include -DFEAT_MZSCHEME -DMZSCHEME_COLLECTS=\"$(MZSCHEME)/collects\"
+ifndef MZSCHEME_COLLECTS
+MZSCHEME_COLLECTS=$(MZSCHEME)/collects
+ifeq (yes, $(UNDER_CYGWIN))
+MZSCHEME_COLLECTS:=$(shell cygpath -m $(MZSCHEME_COLLECTS) | sed -e 's/ /\\ /g')
+endif
+endif
+CFLAGS += -I$(MZSCHEME)/include -DFEAT_MZSCHEME -DMZSCHEME_COLLECTS=\"$(MZSCHEME_COLLECTS)\"
 ifeq (yes, $(DYNAMIC_MZSCHEME))
+ifeq (yes, $(MZSCHEME_PRECISE_GC))
+# Precise GC does not use separate dll
+CFLAGS += -DDYNAMIC_MZSCHEME -DDYNAMIC_MZSCH_DLL=\"lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll\" -DDYNAMIC_MZGC_DLL=\"lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll\"
+else
 CFLAGS += -DDYNAMIC_MZSCHEME -DDYNAMIC_MZSCH_DLL=\"lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll\" -DDYNAMIC_MZGC_DLL=\"libmzgc$(MZSCHEME_VER).dll\"
 endif
+endif
 ifeq (yes, "$(MZSCHEME_DEBUG)")
 CFLAGS += -DMZSCHEME_FORCE_GC
 endif
diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index 6f0b843..df5a748 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -755,43 +755,52 @@
 !ifndef MZSCHEME_VER
 MZSCHEME_VER = 205_000
 !endif
-CFLAGS = $(CFLAGS) -DFEAT_MZSCHEME -I $(MZSCHEME)\include
-!if EXIST("$(MZSCHEME)\collects\scheme\base.ss") \
-      	|| EXIST("$(MZSCHEME)\collects\scheme\base.rkt") \
-      	|| EXIST("$(MZSCHEME)\collects\racket\base.rkt")
-# for MzScheme >= 4 we need to include byte code for basic Scheme stuff
-MZSCHEME_EXTRA_DEP = mzscheme_base.c
-CFLAGS = $(CFLAGS) -DINCLUDE_MZSCHEME_BASE
+!ifndef MZSCHEME_COLLECTS
+MZSCHEME_COLLECTS=$(MZSCHEME)\collects
 !endif
+CFLAGS = $(CFLAGS) -DFEAT_MZSCHEME -I "$(MZSCHEME)\include"
 !if EXIST("$(MZSCHEME)\lib\msvc\libmzsch$(MZSCHEME_VER).lib")
 MZSCHEME_MAIN_LIB=mzsch
 !else
 MZSCHEME_MAIN_LIB=racket
 !endif
-!if EXIST("$(MZSCHEME)\lib\msvc\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib") \
-	&& !EXIST("$(MZSCHEME)\lib\msvc\libmzgc$(MZSCHEME_VER).lib")
+!if (EXIST("$(MZSCHEME)\lib\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll") \
+     && !EXIST("$(MZSCHEME)\lib\libmzgc$(MZSCHEME_VER).dll")) \
+    || (EXIST("$(MZSCHEME)\lib\msvc\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib") \
+        && !EXIST("$(MZSCHEME)\lib\msvc\libmzgc$(MZSCHEME_VER).lib"))
 !message Building with Precise GC
 MZSCHEME_PRECISE_GC = yes
 CFLAGS = $(CFLAGS) -DMZ_PRECISE_GC
 !endif
 !if "$(DYNAMIC_MZSCHEME)" == "yes"
-!if "$(MZSCHEME_PRECISE_GC)" == "yes"
-!error MzScheme with Precise GC cannot be loaded dynamically
-!endif
 !message MzScheme DLLs will be loaded dynamically
-CFLAGS = $(CFLAGS) -DDYNAMIC_MZSCHEME \
-		-DDYNAMIC_MZSCH_DLL=\"lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll\" \
-		-DDYNAMIC_MZGC_DLL=\"libmzgc$(MZSCHEME_VER).dll\"
+CFLAGS = $(CFLAGS) -DDYNAMIC_MZSCHEME
+!if "$(MZSCHEME_PRECISE_GC)" == "yes"
+# Precise GC does not use separate dll
+CFLAGS = $(CFLAGS) \
+	 -DDYNAMIC_MZSCH_DLL=\"lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll\" \
+	 -DDYNAMIC_MZGC_DLL=\"lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll\"
+!else
+CFLAGS = $(CFLAGS) \
+	 -DDYNAMIC_MZSCH_DLL=\"lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).dll\" \
+	 -DDYNAMIC_MZGC_DLL=\"libmzgc$(MZSCHEME_VER).dll\"
+!endif
 !else
 !if "$(MZSCHEME_DEBUG)" == "yes"
 CFLAGS = $(CFLAGS) -DMZSCHEME_FORCE_GC
 !endif
 !if "$(MZSCHEME_PRECISE_GC)" == "yes"
 # Precise GC does not use separate dll
-MZSCHEME_LIB = $(MZSCHEME)\lib\msvc\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib
+!if EXIST("$(MZSCHEME)\lib\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).def")
+# create .lib from .def
+MZSCHEME_LIB = lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib
+MZSCHEME_EXTRA_DEP = lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib
 !else
-MZSCHEME_LIB = $(MZSCHEME)\lib\msvc\libmzgc$(MZSCHEME_VER).lib \
-		$(MZSCHEME)\lib\msvc\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib
+MZSCHEME_LIB = "$(MZSCHEME)\lib\msvc\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib"
+!endif
+!else
+MZSCHEME_LIB = "$(MZSCHEME)\lib\msvc\libmzgc$(MZSCHEME_VER).lib" \
+		"$(MZSCHEME)\lib\msvc\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib"
 !endif
 !endif
 MZSCHEME_OBJ = $(OUTDIR)\if_mzsch.obj
@@ -1059,7 +1068,6 @@
 	- if exist dimm_i.c del dimm_i.c
 	- if exist dimm.tlb del dimm.tlb
 	- if exist dosinst.exe del dosinst.exe
-	- if exist mzscheme_base.c del mzscheme_base.c
 	cd xxd
 	$(MAKE) /NOLOGO -f Make_mvc.mak clean
 	cd ..
@@ -1172,13 +1180,10 @@
 
 $(OUTDIR)/if_mzsch.obj: $(OUTDIR) if_mzsch.c if_mzsch.h $(INCL) $(MZSCHEME_EXTRA_DEP)
 	$(CC) $(CFLAGS) if_mzsch.c \
-		-DMZSCHEME_COLLECTS=\"$(MZSCHEME:\=\\)\\collects\"
-mzscheme_base.c:
-!IF "$(MZSCHEME_MAIN_LIB)" == "racket"
-	$(MZSCHEME)\raco ctool --c-mods mzscheme_base.c ++lib scheme/base
-!ELSE
-	$(MZSCHEME)\mzc --c-mods mzscheme_base.c ++lib scheme/base
-!ENDIF
+		-DMZSCHEME_COLLECTS="\"$(MZSCHEME_COLLECTS:\=\\)\""
+
+lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).lib:
+	lib /DEF:"$(MZSCHEME)\lib\lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).def"
 
 $(OUTDIR)/if_python.obj: $(OUTDIR) if_python.c if_py_both.h $(INCL)
 	$(CC) $(CFLAGS) $(PYTHON_INC) if_python.c
diff --git a/src/auto/configure b/src/auto/configure
index e07d7ec..ed8ca6a 100755
--- a/src/auto/configure
+++ b/src/auto/configure
@@ -5207,6 +5207,7 @@
 
   if test "X$with_plthome" != "X"; then
        vi_cv_path_mzscheme_pfx="$with_plthome"
+       vi_cv_path_mzscheme="${vi_cv_path_mzscheme_pfx}/bin/mzscheme"
   else
     { $as_echo "$as_me:${as_lineno-$LINENO}: checking PLTHOME environment var" >&5
 $as_echo_n "checking PLTHOME environment var... " >&6; }
@@ -5214,6 +5215,7 @@
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: \"$PLTHOME\"" >&5
 $as_echo "\"$PLTHOME\"" >&6; }
 	vi_cv_path_mzscheme_pfx="$PLTHOME"
+	vi_cv_path_mzscheme="${vi_cv_path_mzscheme_pfx}/bin/mzscheme"
     else
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: not set" >&5
 $as_echo "not set" >&6; }
@@ -5285,54 +5287,63 @@
     fi
   fi
 
-  SCHEME_INC=
   if test "X$vi_cv_path_mzscheme_pfx" != "X"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include" >&5
-$as_echo_n "checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include... " >&6; }
-    if test -f "$vi_cv_path_mzscheme_pfx/include/scheme.h"; then
-      SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include
-      { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for racket include directory" >&5
+$as_echo_n "checking for racket include directory... " >&6; }
+    SCHEME_INC=`${vi_cv_path_mzscheme} -e '(require setup/dirs)(let ((p (find-include-dir))) (when (path? p) (display p)))'`
+    if test "X$SCHEME_INC" != "X"; then
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: ${SCHEME_INC}" >&5
+$as_echo "${SCHEME_INC}" >&6; }
     else
-      { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/plt" >&5
-$as_echo_n "checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/plt... " >&6; }
-      if test -f "$vi_cv_path_mzscheme_pfx/include/plt/scheme.h"; then
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: not found" >&5
+$as_echo "not found" >&6; }
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include" >&5
+$as_echo_n "checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include... " >&6; }
+      if test -f "$vi_cv_path_mzscheme_pfx/include/scheme.h"; then
+	SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
 $as_echo "yes" >&6; }
-	SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include/plt
       else
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
 $as_echo "no" >&6; }
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/racket" >&5
-$as_echo_n "checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/racket... " >&6; }
-	if test -f "$vi_cv_path_mzscheme_pfx/include/racket/scheme.h"; then
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/plt" >&5
+$as_echo_n "checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/plt... " >&6; }
+	if test -f "$vi_cv_path_mzscheme_pfx/include/plt/scheme.h"; then
 	  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
 $as_echo "yes" >&6; }
-	  SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include/racket
+	  SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include/plt
 	else
 	  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
 $as_echo "no" >&6; }
-	  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in /usr/include/plt/" >&5
-$as_echo_n "checking if scheme.h can be found in /usr/include/plt/... " >&6; }
-	  if test -f /usr/include/plt/scheme.h; then
+	  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/racket" >&5
+$as_echo_n "checking if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/racket... " >&6; }
+	  if test -f "$vi_cv_path_mzscheme_pfx/include/racket/scheme.h"; then
 	    { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
 $as_echo "yes" >&6; }
-	    SCHEME_INC=/usr/include/plt
+	    SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include/racket
 	  else
 	    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
 $as_echo "no" >&6; }
-	    { $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in /usr/include/racket/" >&5
-$as_echo_n "checking if scheme.h can be found in /usr/include/racket/... " >&6; }
-	    if test -f /usr/include/racket/scheme.h; then
+	    { $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in /usr/include/plt/" >&5
+$as_echo_n "checking if scheme.h can be found in /usr/include/plt/... " >&6; }
+	    if test -f /usr/include/plt/scheme.h; then
 	      { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
 $as_echo "yes" >&6; }
-	      SCHEME_INC=/usr/include/racket
+	      SCHEME_INC=/usr/include/plt
 	    else
 	      { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
 $as_echo "no" >&6; }
-	      vi_cv_path_mzscheme_pfx=
+	      { $as_echo "$as_me:${as_lineno-$LINENO}: checking if scheme.h can be found in /usr/include/racket/" >&5
+$as_echo_n "checking if scheme.h can be found in /usr/include/racket/... " >&6; }
+	      if test -f /usr/include/racket/scheme.h; then
+		{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+		SCHEME_INC=/usr/include/racket
+	      else
+		{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+		vi_cv_path_mzscheme_pfx=
+	      fi
 	    fi
 	  fi
 	fi
@@ -5341,52 +5352,101 @@
   fi
 
   if test "X$vi_cv_path_mzscheme_pfx" != "X"; then
-    if test "x$MACOSX" = "xyes"; then
-      MZSCHEME_LIBS="-framework Racket"
-      MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-    elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libmzscheme3m.a"; then
-      MZSCHEME_LIBS="${vi_cv_path_mzscheme_pfx}/lib/libmzscheme3m.a"
-      MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-    elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libracket3m.a"; then
-      MZSCHEME_LIBS="${vi_cv_path_mzscheme_pfx}/lib/libracket3m.a"
-      MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-    elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libracket.a"; then
-      MZSCHEME_LIBS="${vi_cv_path_mzscheme_pfx}/lib/libracket.a ${vi_cv_path_mzscheme_pfx}/lib/libmzgc.a"
-    elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libmzscheme.a"; then
-      MZSCHEME_LIBS="${vi_cv_path_mzscheme_pfx}/lib/libmzscheme.a ${vi_cv_path_mzscheme_pfx}/lib/libmzgc.a"
+
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for racket lib directory" >&5
+$as_echo_n "checking for racket lib directory... " >&6; }
+    SCHEME_LIB=`${vi_cv_path_mzscheme} -e '(require setup/dirs)(let ((p (find-lib-dir))) (when (path? p) (display p)))'`
+    if test "X$SCHEME_LIB" != "X"; then
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: ${SCHEME_LIB}" >&5
+$as_echo "${SCHEME_LIB}" >&6; }
     else
-            if test -f "${vi_cv_path_mzscheme_pfx}/lib/libmzscheme3m.so"; then
-        MZSCHEME_LIBS="-L${vi_cv_path_mzscheme_pfx}/lib -lmzscheme3m"
-	MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-      elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libracket3m.so"; then
-        MZSCHEME_LIBS="-L${vi_cv_path_mzscheme_pfx}/lib -lracket3m"
-	MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-      elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libracket.so"; then
-        MZSCHEME_LIBS="-L${vi_cv_path_mzscheme_pfx}/lib -lracket -lmzgc"
-      else
-        MZSCHEME_LIBS="-L${vi_cv_path_mzscheme_pfx}/lib -lmzscheme -lmzgc"
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: not found" >&5
+$as_echo "not found" >&6; }
+    fi
+
+    for path in "${vi_cv_path_mzscheme_pfx}/lib" "${SCHEME_LIB}"; do
+      if test "X$path" != "X"; then
+	if test "x$MACOSX" = "xyes"; then
+	  MZSCHEME_LIBS="-framework Racket"
+	  MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	elif test -f "${path}/libmzscheme3m.a"; then
+	  MZSCHEME_LIBS="${path}/libmzscheme3m.a"
+	  MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	elif test -f "${path}/libracket3m.a"; then
+	  MZSCHEME_LIBS="${path}/libracket3m.a"
+	  MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	elif test -f "${path}/libracket.a"; then
+	  MZSCHEME_LIBS="${path}/libracket.a ${path}/libmzgc.a"
+	elif test -f "${path}/libmzscheme.a"; then
+	  MZSCHEME_LIBS="${path}/libmzscheme.a ${path}/libmzgc.a"
+	else
+	  	  if test -f "${path}/libmzscheme3m.so"; then
+	    MZSCHEME_LIBS="-L${path} -lmzscheme3m"
+	    MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	  elif test -f "${path}/libracket3m.so"; then
+	    MZSCHEME_LIBS="-L${path} -lracket3m"
+	    MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	  elif test -f "${path}/libracket.so"; then
+	    MZSCHEME_LIBS="-L${path} -lracket -lmzgc"
+	  else
+	    	    if test "$path" != "$SCHEME_LIB"; then
+	      continue
+	    fi
+	    MZSCHEME_LIBS="-L${path} -lmzscheme -lmzgc"
+	  fi
+	  if test "$GCC" = yes; then
+	    	    	    MZSCHEME_LIBS="${MZSCHEME_LIBS} -Wl,-rpath -Wl,${path}"
+	  elif test "`(uname) 2>/dev/null`" = SunOS &&
+				   uname -r | grep '^5' >/dev/null; then
+	    MZSCHEME_LIBS="${MZSCHEME_LIBS} -R ${path}"
+	  fi
+	fi
       fi
-      if test "$GCC" = yes; then
-			MZSCHEME_LIBS="${MZSCHEME_LIBS} -Wl,-rpath -Wl,${vi_cv_path_mzscheme_pfx}/lib"
-      elif test "`(uname) 2>/dev/null`" = SunOS &&
-			       uname -r | grep '^5' >/dev/null; then
-	MZSCHEME_LIBS="${MZSCHEME_LIBS} -R ${vi_cv_path_mzscheme_pfx}/lib"
+      if test "X$MZSCHEME_LIBS" != "X"; then
+	break
       fi
+    done
+
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking if racket requires -pthread" >&5
+$as_echo_n "checking if racket requires -pthread... " >&6; }
+    if test "X$SCHEME_LIB" != "X" && $FGREP -e -pthread "$SCHEME_LIB/buildinfo" >/dev/null ; then
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+      MZSCHEME_LIBS="${MZSCHEME_LIBS} -pthread"
+      MZSCHEME_CFLAGS="${MZSCHEME_CFLAGS} -pthread"
+    else
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+    fi
+
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for racket config directory" >&5
+$as_echo_n "checking for racket config directory... " >&6; }
+    SCHEME_CONFIGDIR=`${vi_cv_path_mzscheme} -e '(require setup/dirs)(let ((p (find-config-dir))) (when (path? p) (display p)))'`
+    if test "X$SCHEME_CONFIGDIR" != "X"; then
+      MZSCHEME_CFLAGS="${MZSCHEME_CFLAGS} -DMZSCHEME_CONFIGDIR='\"${SCHEME_CONFIGDIR}\"'"
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: ${SCHEME_CONFIGDIR}" >&5
+$as_echo "${SCHEME_CONFIGDIR}" >&6; }
+    else
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: not found" >&5
+$as_echo "not found" >&6; }
     fi
 
     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for racket collects directory" >&5
 $as_echo_n "checking for racket collects directory... " >&6; }
-    if test -d "$vi_cv_path_mzscheme_pfx/lib/plt/collects"; then
-      SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/lib/plt/
-    else
-      if test -d "$vi_cv_path_mzscheme_pfx/lib/racket/collects"; then
-	SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/lib/racket/
+    SCHEME_COLLECTS=`${vi_cv_path_mzscheme} -e '(require setup/dirs)(let ((p (find-collects-dir))) (when (path? p) (let-values (((base _1 _2) (split-path p))) (display base))))'`
+    if test "X$SCHEME_COLLECTS" = "X"; then
+      if test -d "$vi_cv_path_mzscheme_pfx/lib/plt/collects"; then
+	SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/lib/plt/
       else
-	if test -d "$vi_cv_path_mzscheme_pfx/share/racket/collects"; then
-	  SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/share/racket/
+	if test -d "$vi_cv_path_mzscheme_pfx/lib/racket/collects"; then
+	  SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/lib/racket/
 	else
-	  if test -d "$vi_cv_path_mzscheme_pfx/collects"; then
-	    SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/
+	  if test -d "$vi_cv_path_mzscheme_pfx/share/racket/collects"; then
+	    SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/share/racket/
+	  else
+	    if test -d "$vi_cv_path_mzscheme_pfx/collects"; then
+	      SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/
+	    fi
 	  fi
 	fi
       fi
@@ -5420,7 +5480,6 @@
     fi
     if test "X$MZSCHEME_EXTRA" != "X" ; then
             MZSCHEME_CFLAGS="${MZSCHEME_CFLAGS} -DINCLUDE_MZSCHEME_BASE"
-      MZSCHEME_MZC="${vi_cv_path_mzscheme_pfx}/bin/mzc"
       { $as_echo "$as_me:${as_lineno-$LINENO}: result: needed" >&5
 $as_echo "needed" >&6; }
     else
diff --git a/src/configure.in b/src/configure.in
index 6048e8f..adb30c4 100644
--- a/src/configure.in
+++ b/src/configure.in
@@ -695,11 +695,13 @@
 
   if test "X$with_plthome" != "X"; then
        vi_cv_path_mzscheme_pfx="$with_plthome"
+       vi_cv_path_mzscheme="${vi_cv_path_mzscheme_pfx}/bin/mzscheme"
   else
     AC_MSG_CHECKING(PLTHOME environment var)
     if test "X$PLTHOME" != "X"; then
 	AC_MSG_RESULT("$PLTHOME")
 	vi_cv_path_mzscheme_pfx="$PLTHOME"
+	vi_cv_path_mzscheme="${vi_cv_path_mzscheme_pfx}/bin/mzscheme"
     else
 	AC_MSG_RESULT(not set)
 	dnl -- try to find MzScheme executable
@@ -731,39 +733,45 @@
     fi
   fi
 
-  SCHEME_INC=
   if test "X$vi_cv_path_mzscheme_pfx" != "X"; then
-    AC_MSG_CHECKING(if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include)
-    if test -f "$vi_cv_path_mzscheme_pfx/include/scheme.h"; then
-      SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include
-      AC_MSG_RESULT(yes)
+    AC_MSG_CHECKING(for racket include directory)
+    SCHEME_INC=`${vi_cv_path_mzscheme} -e '(require setup/dirs)(let ((p (find-include-dir))) (when (path? p) (display p)))'`
+    if test "X$SCHEME_INC" != "X"; then
+      AC_MSG_RESULT(${SCHEME_INC})
     else
-      AC_MSG_RESULT(no)
-      AC_MSG_CHECKING(if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/plt)
-      if test -f "$vi_cv_path_mzscheme_pfx/include/plt/scheme.h"; then
+      AC_MSG_RESULT(not found)
+      AC_MSG_CHECKING(if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include)
+      if test -f "$vi_cv_path_mzscheme_pfx/include/scheme.h"; then
+	SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include
 	AC_MSG_RESULT(yes)
-	SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include/plt
       else
 	AC_MSG_RESULT(no)
-	AC_MSG_CHECKING(if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/racket)
-	if test -f "$vi_cv_path_mzscheme_pfx/include/racket/scheme.h"; then
+	AC_MSG_CHECKING(if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/plt)
+	if test -f "$vi_cv_path_mzscheme_pfx/include/plt/scheme.h"; then
 	  AC_MSG_RESULT(yes)
-	  SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include/racket
+	  SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include/plt
 	else
 	  AC_MSG_RESULT(no)
-	  AC_MSG_CHECKING(if scheme.h can be found in /usr/include/plt/)
-	  if test -f /usr/include/plt/scheme.h; then
+	  AC_MSG_CHECKING(if scheme.h can be found in $vi_cv_path_mzscheme_pfx/include/racket)
+	  if test -f "$vi_cv_path_mzscheme_pfx/include/racket/scheme.h"; then
 	    AC_MSG_RESULT(yes)
-	    SCHEME_INC=/usr/include/plt
+	    SCHEME_INC=${vi_cv_path_mzscheme_pfx}/include/racket
 	  else
 	    AC_MSG_RESULT(no)
-	    AC_MSG_CHECKING(if scheme.h can be found in /usr/include/racket/)
-	    if test -f /usr/include/racket/scheme.h; then
+	    AC_MSG_CHECKING(if scheme.h can be found in /usr/include/plt/)
+	    if test -f /usr/include/plt/scheme.h; then
 	      AC_MSG_RESULT(yes)
-	      SCHEME_INC=/usr/include/racket
+	      SCHEME_INC=/usr/include/plt
 	    else
 	      AC_MSG_RESULT(no)
-	      vi_cv_path_mzscheme_pfx=
+	      AC_MSG_CHECKING(if scheme.h can be found in /usr/include/racket/)
+	      if test -f /usr/include/racket/scheme.h; then
+		AC_MSG_RESULT(yes)
+		SCHEME_INC=/usr/include/racket
+	      else
+		AC_MSG_RESULT(no)
+		vi_cv_path_mzscheme_pfx=
+	      fi
 	    fi
 	  fi
 	fi
@@ -772,54 +780,95 @@
   fi
 
   if test "X$vi_cv_path_mzscheme_pfx" != "X"; then
-    if test "x$MACOSX" = "xyes"; then
-      MZSCHEME_LIBS="-framework Racket"
-      MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-    elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libmzscheme3m.a"; then
-      MZSCHEME_LIBS="${vi_cv_path_mzscheme_pfx}/lib/libmzscheme3m.a"
-      MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-    elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libracket3m.a"; then
-      MZSCHEME_LIBS="${vi_cv_path_mzscheme_pfx}/lib/libracket3m.a"
-      MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-    elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libracket.a"; then
-      MZSCHEME_LIBS="${vi_cv_path_mzscheme_pfx}/lib/libracket.a ${vi_cv_path_mzscheme_pfx}/lib/libmzgc.a"
-    elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libmzscheme.a"; then
-      MZSCHEME_LIBS="${vi_cv_path_mzscheme_pfx}/lib/libmzscheme.a ${vi_cv_path_mzscheme_pfx}/lib/libmzgc.a"
+
+    AC_MSG_CHECKING(for racket lib directory)
+    SCHEME_LIB=`${vi_cv_path_mzscheme} -e '(require setup/dirs)(let ((p (find-lib-dir))) (when (path? p) (display p)))'`
+    if test "X$SCHEME_LIB" != "X"; then
+      AC_MSG_RESULT(${SCHEME_LIB})
     else
-      dnl Using shared objects
-      if test -f "${vi_cv_path_mzscheme_pfx}/lib/libmzscheme3m.so"; then
-        MZSCHEME_LIBS="-L${vi_cv_path_mzscheme_pfx}/lib -lmzscheme3m"
-	MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-      elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libracket3m.so"; then
-        MZSCHEME_LIBS="-L${vi_cv_path_mzscheme_pfx}/lib -lracket3m"
-	MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
-      elif test -f "${vi_cv_path_mzscheme_pfx}/lib/libracket.so"; then
-        MZSCHEME_LIBS="-L${vi_cv_path_mzscheme_pfx}/lib -lracket -lmzgc"
-      else
-        MZSCHEME_LIBS="-L${vi_cv_path_mzscheme_pfx}/lib -lmzscheme -lmzgc"
+      AC_MSG_RESULT(not found)
+    fi
+
+    for path in "${vi_cv_path_mzscheme_pfx}/lib" "${SCHEME_LIB}"; do
+      if test "X$path" != "X"; then
+	if test "x$MACOSX" = "xyes"; then
+	  MZSCHEME_LIBS="-framework Racket"
+	  MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	elif test -f "${path}/libmzscheme3m.a"; then
+	  MZSCHEME_LIBS="${path}/libmzscheme3m.a"
+	  MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	elif test -f "${path}/libracket3m.a"; then
+	  MZSCHEME_LIBS="${path}/libracket3m.a"
+	  MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	elif test -f "${path}/libracket.a"; then
+	  MZSCHEME_LIBS="${path}/libracket.a ${path}/libmzgc.a"
+	elif test -f "${path}/libmzscheme.a"; then
+	  MZSCHEME_LIBS="${path}/libmzscheme.a ${path}/libmzgc.a"
+	else
+	  dnl Using shared objects
+	  if test -f "${path}/libmzscheme3m.so"; then
+	    MZSCHEME_LIBS="-L${path} -lmzscheme3m"
+	    MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	  elif test -f "${path}/libracket3m.so"; then
+	    MZSCHEME_LIBS="-L${path} -lracket3m"
+	    MZSCHEME_CFLAGS="-DMZ_PRECISE_GC"
+	  elif test -f "${path}/libracket.so"; then
+	    MZSCHEME_LIBS="-L${path} -lracket -lmzgc"
+	  else
+	    dnl try next until last
+	    if test "$path" != "$SCHEME_LIB"; then
+	      continue
+	    fi
+	    MZSCHEME_LIBS="-L${path} -lmzscheme -lmzgc"
+	  fi
+	  if test "$GCC" = yes; then
+	    dnl Make Vim remember the path to the library.  For when it's not in
+	    dnl $LD_LIBRARY_PATH.
+	    MZSCHEME_LIBS="${MZSCHEME_LIBS} -Wl,-rpath -Wl,${path}"
+	  elif test "`(uname) 2>/dev/null`" = SunOS &&
+				   uname -r | grep '^5' >/dev/null; then
+	    MZSCHEME_LIBS="${MZSCHEME_LIBS} -R ${path}"
+	  fi
+	fi
       fi
-      if test "$GCC" = yes; then
-	dnl Make Vim remember the path to the library.  For when it's not in
-	dnl $LD_LIBRARY_PATH.
-	MZSCHEME_LIBS="${MZSCHEME_LIBS} -Wl,-rpath -Wl,${vi_cv_path_mzscheme_pfx}/lib"
-      elif test "`(uname) 2>/dev/null`" = SunOS &&
-			       uname -r | grep '^5' >/dev/null; then
-	MZSCHEME_LIBS="${MZSCHEME_LIBS} -R ${vi_cv_path_mzscheme_pfx}/lib"
+      if test "X$MZSCHEME_LIBS" != "X"; then
+	break
       fi
+    done
+
+    AC_MSG_CHECKING([if racket requires -pthread])
+    if test "X$SCHEME_LIB" != "X" && $FGREP -e -pthread "$SCHEME_LIB/buildinfo" >/dev/null ; then
+      AC_MSG_RESULT(yes)
+      MZSCHEME_LIBS="${MZSCHEME_LIBS} -pthread"
+      MZSCHEME_CFLAGS="${MZSCHEME_CFLAGS} -pthread"
+    else
+      AC_MSG_RESULT(no)
+    fi
+
+    AC_MSG_CHECKING(for racket config directory)
+    SCHEME_CONFIGDIR=`${vi_cv_path_mzscheme} -e '(require setup/dirs)(let ((p (find-config-dir))) (when (path? p) (display p)))'`
+    if test "X$SCHEME_CONFIGDIR" != "X"; then
+      MZSCHEME_CFLAGS="${MZSCHEME_CFLAGS} -DMZSCHEME_CONFIGDIR='\"${SCHEME_CONFIGDIR}\"'"
+      AC_MSG_RESULT(${SCHEME_CONFIGDIR})
+    else
+      AC_MSG_RESULT(not found)
     fi
 
     AC_MSG_CHECKING(for racket collects directory)
-    if test -d "$vi_cv_path_mzscheme_pfx/lib/plt/collects"; then
-      SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/lib/plt/
-    else
-      if test -d "$vi_cv_path_mzscheme_pfx/lib/racket/collects"; then
-	SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/lib/racket/
+    SCHEME_COLLECTS=`${vi_cv_path_mzscheme} -e '(require setup/dirs)(let ((p (find-collects-dir))) (when (path? p) (let-values (((base _1 _2) (split-path p))) (display base))))'`
+    if test "X$SCHEME_COLLECTS" = "X"; then
+      if test -d "$vi_cv_path_mzscheme_pfx/lib/plt/collects"; then
+	SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/lib/plt/
       else
-	if test -d "$vi_cv_path_mzscheme_pfx/share/racket/collects"; then
-	  SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/share/racket/
+	if test -d "$vi_cv_path_mzscheme_pfx/lib/racket/collects"; then
+	  SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/lib/racket/
 	else
-	  if test -d "$vi_cv_path_mzscheme_pfx/collects"; then
-	    SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/
+	  if test -d "$vi_cv_path_mzscheme_pfx/share/racket/collects"; then
+	    SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/share/racket/
+	  else
+	    if test -d "$vi_cv_path_mzscheme_pfx/collects"; then
+	      SCHEME_COLLECTS=$vi_cv_path_mzscheme_pfx/
+	    fi
 	  fi
 	fi
       fi
@@ -851,7 +900,6 @@
     if test "X$MZSCHEME_EXTRA" != "X" ; then
       dnl need to generate bytecode for MzScheme base
       MZSCHEME_CFLAGS="${MZSCHEME_CFLAGS} -DINCLUDE_MZSCHEME_BASE"
-      MZSCHEME_MZC="${vi_cv_path_mzscheme_pfx}/bin/mzc"
       AC_MSG_RESULT(needed)
     else
       AC_MSG_RESULT(not needed)
diff --git a/src/if_mzsch.c b/src/if_mzsch.c
index 287ab1a..ea04705 100644
--- a/src/if_mzsch.c
+++ b/src/if_mzsch.c
@@ -29,6 +29,27 @@
  * depend". */
 #if defined(FEAT_MZSCHEME) || defined(PROTO)
 
+/*
+ * scheme_register_tls_space is only available on 32-bit Windows until
+ * racket-6.3.  See
+ * http://docs.racket-lang.org/inside/im_memoryalloc.html?q=scheme_register_tls_space
+ */
+#if MZSCHEME_VERSION_MAJOR >= 500 && defined(WIN32) \
+	&& defined(USE_THREAD_LOCAL) \
+	&& (!defined(_WIN64) || MZSCHEME_VERSION_MAJOR >= 603)
+# define HAVE_TLS_SPACE 1
+#endif
+
+/*
+ * Since version 4.x precise GC requires trampolined startup.
+ * Futures and places in version 5.x need it too.
+ */
+#if defined(MZ_PRECISE_GC) && MZSCHEME_VERSION_MAJOR >= 400 \
+    || MZSCHEME_VERSION_MAJOR >= 500 \
+	&& (defined(MZ_USE_FUTURES) || defined(MZ_USE_PLACES))
+# define TRAMPOLINED_MZVIM_STARTUP
+#endif
+
 /* Base data structures */
 #define SCHEME_VIMBUFFERP(obj)  SAME_TYPE(SCHEME_TYPE(obj), mz_buffer_type)
 #define SCHEME_VIMWINDOWP(obj)  SAME_TYPE(SCHEME_TYPE(obj), mz_window_type)
@@ -138,9 +159,9 @@
  */
 static int vim_error_check(void);
 static int do_mzscheme_command(exarg_T *, void *, Scheme_Closed_Prim *what);
-static void startup_mzscheme(void);
+static int startup_mzscheme(void);
 static char *string_to_line(Scheme_Object *obj);
-#if MZSCHEME_VERSION_MAJOR >= 500
+#if MZSCHEME_VERSION_MAJOR >= 501
 # define OUTPUT_LEN_TYPE intptr_t
 #else
 # define OUTPUT_LEN_TYPE long
@@ -237,7 +258,7 @@
 static Scheme_Thread **dll_scheme_current_thread_ptr;
 
 static void (**dll_scheme_console_printf_ptr)(char *str, ...);
-static void (**dll_scheme_console_output_ptr)(char *str, long len);
+static void (**dll_scheme_console_output_ptr)(char *str, OUTPUT_LEN_TYPE len);
 static void (**dll_scheme_notify_multithread_ptr)(int on);
 
 static void *(*dll_GC_malloc)(size_t size_in_bytes);
@@ -255,6 +276,7 @@
 static Scheme_Object *(*dll_scheme_builtin_value)(const char *name);
 # if MZSCHEME_VERSION_MAJOR >= 299
 static Scheme_Object *(*dll_scheme_byte_string_to_char_string)(Scheme_Object *s);
+static Scheme_Object *(*dll_scheme_make_path)(const char *chars);
 # endif
 static void (*dll_scheme_close_input_port)(Scheme_Object *port);
 static void (*dll_scheme_count_lines)(Scheme_Object *port);
@@ -264,7 +286,7 @@
 static Scheme_Object *(*dll_scheme_current_continuation_marks)(Scheme_Object *prompt_tag);
 #endif
 static void (*dll_scheme_display)(Scheme_Object *obj, Scheme_Object *port);
-static char *(*dll_scheme_display_to_string)(Scheme_Object *obj, long *len);
+static char *(*dll_scheme_display_to_string)(Scheme_Object *obj, OUTPUT_LEN_TYPE *len);
 static int (*dll_scheme_eq)(Scheme_Object *obj1, Scheme_Object *obj2);
 static Scheme_Object *(*dll_scheme_do_eval)(Scheme_Object *obj,
 	int _num_rands, Scheme_Object **rands, int val);
@@ -280,7 +302,7 @@
 	Scheme_Object **argv, long *rlen);
 # else
 static char *(*dll_scheme_format_utf8)(char *format, int flen, int argc,
-	Scheme_Object **argv, long *rlen);
+	Scheme_Object **argv, OUTPUT_LEN_TYPE *rlen);
 static Scheme_Object *(*dll_scheme_get_param)(Scheme_Config *c, int pos);
 # endif
 static void (*dll_scheme_gc_ptr_ok)(void *p);
@@ -289,7 +311,7 @@
 	long *len);
 # else
 static char *(*dll_scheme_get_sized_byte_string_output)(Scheme_Object *,
-	long *len);
+	OUTPUT_LEN_TYPE *len);
 # endif
 static Scheme_Object *(*dll_scheme_intern_symbol)(const char *name);
 static Scheme_Object *(*dll_scheme_lookup_global)(Scheme_Object *symbol,
@@ -354,10 +376,34 @@
 static Scheme_Object *(*dll_scheme_hash_get)(Scheme_Hash_Table *table,
 	Scheme_Object *key);
 static Scheme_Object *(*dll_scheme_make_double)(double d);
-# ifdef INCLUDE_MZSCHEME_BASE
 static Scheme_Object *(*dll_scheme_make_sized_byte_string)(char *chars,
 	long len, int copy);
 static Scheme_Object *(*dll_scheme_namespace_require)(Scheme_Object *req);
+static Scheme_Object *(*dll_scheme_dynamic_wind)(void (*pre)(void *), Scheme_Object *(* volatile act)(void *), void (* volatile post)(void *), Scheme_Object *(*jmp_handler)(void *), void * volatile data);
+# ifdef MZ_PRECISE_GC
+static void *(*dll_GC_malloc_one_tagged)(size_t size_in_bytes);
+static void (*dll_GC_register_traversers)(short tag, Size_Proc size, Mark_Proc mark, Fixup_Proc fixup, int is_constant_size, int is_atomic);
+# endif
+# if MZSCHEME_VERSION_MAJOR >= 400
+static void (*dll_scheme_init_collection_paths)(Scheme_Env *global_env, Scheme_Object *extra_dirs);
+static void **(*dll_scheme_malloc_immobile_box)(void *p);
+static void (*dll_scheme_free_immobile_box)(void **b);
+# endif
+# if MZSCHEME_VERSION_MAJOR >= 500
+#  ifdef TRAMPOLINED_MZVIM_STARTUP
+static int (*dll_scheme_main_setup)(int no_auto_statics, Scheme_Env_Main _main, int argc, char **argv);
+#   if defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS) || MZSCHEME_VERSION_MAJOR >= 603
+static void (*dll_scheme_register_tls_space)(void *tls_space, int _tls_index);
+#   endif
+#  endif
+#  if defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS) || defined(IMPLEMENT_THREAD_LOCAL_EXTERNALLY_VIA_PROC)
+static Thread_Local_Variables *(*dll_scheme_external_get_thread_local_variables)(void);
+#  endif
+# endif
+# if MZSCHEME_VERSION_MAJOR >= 600
+static void (*dll_scheme_embedded_load)(intptr_t len, const char *s, int predefined);
+static void (*dll_scheme_register_embedded_load)(intptr_t len, const char *s);
+static void (*dll_scheme_set_config_path)(Scheme_Object *p);
 # endif
 
 /* arrays are imported directly */
@@ -368,7 +414,9 @@
 # define scheme_true dll_scheme_true
 
 /* pointers are GetProceAddress'ed as pointers to pointer */
-# define scheme_current_thread (*dll_scheme_current_thread_ptr)
+#if !defined(USE_THREAD_LOCAL) && !defined(LINK_EXTENSIONS_BY_TABLE)
+#  define scheme_current_thread (*dll_scheme_current_thread_ptr)
+# endif
 # define scheme_console_printf (*dll_scheme_console_printf_ptr)
 # define scheme_console_output (*dll_scheme_console_output_ptr)
 # define scheme_notify_multithread (*dll_scheme_notify_multithread_ptr)
@@ -384,6 +432,7 @@
 # define scheme_builtin_value dll_scheme_builtin_value
 # if MZSCHEME_VERSION_MAJOR >= 299
 #  define scheme_byte_string_to_char_string dll_scheme_byte_string_to_char_string
+#  define scheme_make_path dll_scheme_make_path
 # endif
 # define scheme_check_threads dll_scheme_check_threads
 # define scheme_close_input_port dll_scheme_close_input_port
@@ -455,9 +504,39 @@
 # define scheme_hash_set dll_scheme_hash_set
 # define scheme_hash_get dll_scheme_hash_get
 # define scheme_make_double dll_scheme_make_double
-# ifdef INCLUDE_MZSCHEME_BASE
-#  define scheme_make_sized_byte_string dll_scheme_make_sized_byte_string
-#  define scheme_namespace_require dll_scheme_namespace_require
+# define scheme_make_sized_byte_string dll_scheme_make_sized_byte_string
+# define scheme_namespace_require dll_scheme_namespace_require
+# define scheme_dynamic_wind dll_scheme_dynamic_wind
+# ifdef MZ_PRECISE_GC
+#  define GC_malloc_one_tagged dll_GC_malloc_one_tagged
+#  define GC_register_traversers dll_GC_register_traversers
+# endif
+# if MZSCHEME_VERSION_MAJOR >= 400
+#  ifdef TRAMPOLINED_MZVIM_STARTUP
+#   define scheme_main_setup dll_scheme_main_setup
+#   if defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS) || MZSCHEME_VERSION_MAJOR >= 603
+#    define scheme_register_tls_space dll_scheme_register_tls_space
+#   endif
+#  endif
+#  define scheme_init_collection_paths dll_scheme_init_collection_paths
+#  define scheme_malloc_immobile_box dll_scheme_malloc_immobile_box
+#  define scheme_free_immobile_box dll_scheme_free_immobile_box
+# endif
+# if MZSCHEME_VERSION_MAJOR >= 600
+#  define scheme_embedded_load dll_scheme_embedded_load
+#  define scheme_register_embedded_load dll_scheme_register_embedded_load
+#  define scheme_set_config_path dll_scheme_set_config_path
+# endif
+
+# if MZSCHEME_VERSION_MAJOR >= 500
+#  if defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS) || defined(IMPLEMENT_THREAD_LOCAL_EXTERNALLY_VIA_PROC)
+/* define as function for macro in schshread.h */
+Thread_Local_Variables *
+scheme_external_get_thread_local_variables(void)
+{
+    return dll_scheme_external_get_thread_local_variables();
+}
+#  endif
 # endif
 
 typedef struct
@@ -477,7 +556,9 @@
     {"scheme_void", (void **)&dll_scheme_void},
     {"scheme_null", (void **)&dll_scheme_null},
     {"scheme_true", (void **)&dll_scheme_true},
+#if !defined(USE_THREAD_LOCAL) && !defined(LINK_EXTENSIONS_BY_TABLE)
     {"scheme_current_thread", (void **)&dll_scheme_current_thread_ptr},
+#endif
     {"scheme_console_printf", (void **)&dll_scheme_console_printf_ptr},
     {"scheme_console_output", (void **)&dll_scheme_console_output_ptr},
     {"scheme_notify_multithread",
@@ -488,6 +569,7 @@
     {"scheme_basic_env", (void **)&dll_scheme_basic_env},
 # if MZSCHEME_VERSION_MAJOR >= 299
     {"scheme_byte_string_to_char_string", (void **)&dll_scheme_byte_string_to_char_string},
+    {"scheme_make_path", (void **)&dll_scheme_make_path},
 # endif
     {"scheme_builtin_value", (void **)&dll_scheme_builtin_value},
     {"scheme_check_threads", (void **)&dll_scheme_check_threads},
@@ -564,10 +646,34 @@
     {"scheme_hash_set", (void **)&dll_scheme_hash_set},
     {"scheme_hash_get", (void **)&dll_scheme_hash_get},
     {"scheme_make_double", (void **)&dll_scheme_make_double},
-# ifdef INCLUDE_MZSCHEME_BASE
     {"scheme_make_sized_byte_string", (void **)&dll_scheme_make_sized_byte_string},
     {"scheme_namespace_require", (void **)&dll_scheme_namespace_require},
-#endif
+    {"scheme_dynamic_wind", (void **)&dll_scheme_dynamic_wind},
+# ifdef MZ_PRECISE_GC
+    {"GC_malloc_one_tagged", (void **)&dll_GC_malloc_one_tagged},
+    {"GC_register_traversers", (void **)&dll_GC_register_traversers},
+# endif
+# if MZSCHEME_VERSION_MAJOR >= 400
+#  ifdef TRAMPOLINED_MZVIM_STARTUP
+    {"scheme_main_setup", (void **)&dll_scheme_main_setup},
+#   if defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS) || MZSCHEME_VERSION_MAJOR >= 603
+    {"scheme_register_tls_space", (void **)&dll_scheme_register_tls_space},
+#   endif
+#  endif
+    {"scheme_init_collection_paths", (void **)&dll_scheme_init_collection_paths},
+    {"scheme_malloc_immobile_box", (void **)&dll_scheme_malloc_immobile_box},
+    {"scheme_free_immobile_box", (void **)&dll_scheme_free_immobile_box},
+# endif
+# if MZSCHEME_VERSION_MAJOR >= 500
+#  if defined(IMPLEMENT_THREAD_LOCAL_VIA_WIN_TLS) || defined(IMPLEMENT_THREAD_LOCAL_EXTERNALLY_VIA_PROC)
+    {"scheme_external_get_thread_local_variables", (void **)&dll_scheme_external_get_thread_local_variables},
+#  endif
+# endif
+# if MZSCHEME_VERSION_MAJOR >= 600
+    {"scheme_embedded_load", (void **)&dll_scheme_embedded_load},
+    {"scheme_register_embedded_load", (void **)&dll_scheme_register_embedded_load},
+    {"scheme_set_config_path", (void **)&dll_scheme_set_config_path},
+# endif
     {NULL, NULL}};
 
 static HINSTANCE hMzGC = 0;
@@ -687,8 +793,6 @@
 /* need to put it here for dynamic stuff to work */
 #if defined(INCLUDE_MZSCHEME_BASE)
 # include "mzscheme_base.c"
-#elif MZSCHEME_VERSION_MAJOR >= 400
-# error MzScheme >=4 must include mzscheme_base.c, for MinGW32 you need to define MZSCHEME_GENERATE_BASE=yes
 #endif
 
 /*
@@ -701,6 +805,10 @@
 static Scheme_Type mz_window_type;
 
 static int initialized = FALSE;
+#ifdef DYNAMIC_MZSCHEME
+static int disabled = FALSE;
+#endif
+static int load_base_module_failed = FALSE;
 
 /* global environment */
 static Scheme_Env    *environment = NULL;
@@ -846,38 +954,43 @@
     void
 mzscheme_end(void)
 {
+    /* We can not unload the DLL.  Racket's thread might be still alive. */
+#if 0
 #ifdef DYNAMIC_MZSCHEME
     dynamic_mzscheme_end();
 #endif
+#endif
 }
 
-/*
- * scheme_register_tls_space is only available on 32-bit Windows.
- * See http://docs.racket-lang.org/inside/im_memoryalloc.html?q=scheme_register_tls_space
- */
-#if MZSCHEME_VERSION_MAJOR >= 500 && defined(WIN32) \
-	&& defined(USE_THREAD_LOCAL) && !defined(_WIN64)
-# define HAVE_TLS_SPACE 1
+#if HAVE_TLS_SPACE
+# if defined(_MSC_VER)
 static __declspec(thread) void *tls_space;
-#endif
-
-/*
- * Since version 4.x precise GC requires trampolined startup.
- * Futures and places in version 5.x need it too.
- */
-#if defined(MZ_PRECISE_GC) && MZSCHEME_VERSION_MAJOR >= 400 \
-    || MZSCHEME_VERSION_MAJOR >= 500 && (defined(MZ_USE_FUTURES) || defined(MZ_USE_PLACES))
-# ifdef DYNAMIC_MZSCHEME
-#  error Precise GC v.4+ or Racket with futures/places do not support dynamic MzScheme
+extern intptr_t _tls_index;
+# elif defined(__MINGW32__)
+static __thread void *tls_space;
+extern intptr_t _tls_index;
+# else
+static THREAD_LOCAL void *tls_space;
+static intptr_t _tls_index = 0;
 # endif
-# define TRAMPOLINED_MZVIM_STARTUP
 #endif
 
     int
 mzscheme_main(int argc, char** argv)
 {
+#ifdef DYNAMIC_MZSCHEME
+    /*
+     * Racket requires trampolined startup.  We can not load it later.
+     * If dynamic dll loading is failed, disable it.
+     */
+    if (!mzscheme_enabled(FALSE))
+    {
+	disabled = TRUE;
+	return vim_main2(argc, argv);
+    }
+#endif
 #ifdef HAVE_TLS_SPACE
-    scheme_register_tls_space(&tls_space, 0);
+    scheme_register_tls_space(&tls_space, _tls_index);
 #endif
 #ifdef TRAMPOLINED_MZVIM_STARTUP
     return scheme_main_setup(TRUE, mzscheme_env_main, argc, argv);
@@ -919,7 +1032,21 @@
     return vim_main_result;
 }
 
-    static void
+    static Scheme_Object*
+load_base_module(void *data)
+{
+    scheme_namespace_require(scheme_intern_symbol((char *)data));
+    return scheme_null;
+}
+
+    static Scheme_Object *
+load_base_module_on_error(void *data)
+{
+    load_base_module_failed = TRUE;
+    return scheme_null;
+}
+
+    static int
 startup_mzscheme(void)
 {
 #ifndef TRAMPOLINED_MZVIM_STARTUP
@@ -942,87 +1069,45 @@
     MZ_GC_CHECK();
 
 #ifdef INCLUDE_MZSCHEME_BASE
-    {
-	/*
-	 * versions 4.x do not provide Scheme bindings by default
-	 * we need to add them explicitly
-	 */
-	Scheme_Object *scheme_base_symbol = NULL;
-	MZ_GC_DECL_REG(1);
-	MZ_GC_VAR_IN_REG(0, scheme_base_symbol);
-	MZ_GC_REG();
-	/* invoke function from generated and included mzscheme_base.c */
-	declare_modules(environment);
-	scheme_base_symbol = scheme_intern_symbol("scheme/base");
-	MZ_GC_CHECK();
-	scheme_namespace_require(scheme_base_symbol);
-	MZ_GC_CHECK();
-	MZ_GC_UNREG();
-    }
+    /* invoke function from generated and included mzscheme_base.c */
+    declare_modules(environment);
 #endif
-    register_vim_exn();
-    /* use new environment to initialise exception handling */
-    init_exn_catching_apply();
 
-    /* redirect output */
-    scheme_console_output = do_output;
-    scheme_console_printf = do_printf;
-
-#ifdef MZSCHEME_COLLECTS
     /* setup 'current-library-collection-paths' parameter */
 # if MZSCHEME_VERSION_MAJOR >= 299
-#  ifdef MACOS
     {
-	Scheme_Object	*coll_byte_string = NULL;
-	Scheme_Object	*coll_char_string = NULL;
-	Scheme_Object	*coll_path = NULL;
+	Scheme_Object *coll_path = NULL;
+	int mustfree = FALSE;
+	char_u *s;
 
-	MZ_GC_DECL_REG(3);
-	MZ_GC_VAR_IN_REG(0, coll_byte_string);
-	MZ_GC_VAR_IN_REG(1, coll_char_string);
-	MZ_GC_VAR_IN_REG(2, coll_path);
+	MZ_GC_DECL_REG(1);
+	MZ_GC_VAR_IN_REG(0, coll_path);
 	MZ_GC_REG();
-	coll_byte_string = scheme_make_byte_string(MZSCHEME_COLLECTS);
-	MZ_GC_CHECK();
-	coll_char_string = scheme_byte_string_to_char_string(coll_byte_string);
-	MZ_GC_CHECK();
-	coll_path = scheme_char_string_to_path(coll_char_string);
-	MZ_GC_CHECK();
-	scheme_set_collects_path(coll_path);
-	MZ_GC_CHECK();
-	MZ_GC_UNREG();
-    }
-#  else
-   {
-	Scheme_Object	*coll_byte_string = NULL;
-	Scheme_Object	*coll_char_string = NULL;
-	Scheme_Object	*coll_path = NULL;
-	Scheme_Object	*coll_pair = NULL;
-	Scheme_Config	*config = NULL;
-
-	MZ_GC_DECL_REG(5);
-	MZ_GC_VAR_IN_REG(0, coll_byte_string);
-	MZ_GC_VAR_IN_REG(1, coll_char_string);
-	MZ_GC_VAR_IN_REG(2, coll_path);
-	MZ_GC_VAR_IN_REG(3, coll_pair);
-	MZ_GC_VAR_IN_REG(4, config);
-	MZ_GC_REG();
-	coll_byte_string = scheme_make_byte_string(MZSCHEME_COLLECTS);
-	MZ_GC_CHECK();
-	coll_char_string = scheme_byte_string_to_char_string(coll_byte_string);
-	MZ_GC_CHECK();
-	coll_path = scheme_char_string_to_path(coll_char_string);
-	MZ_GC_CHECK();
-	coll_pair = scheme_make_pair(coll_path, scheme_null);
-	MZ_GC_CHECK();
-	config = scheme_current_config();
-	MZ_GC_CHECK();
-	scheme_set_param(config, MZCONFIG_COLLECTION_PATHS, coll_pair);
-	MZ_GC_CHECK();
-	MZ_GC_UNREG();
-    }
+	/* workaround for dynamic loading on windows */
+	s = vim_getenv("PLTCOLLECTS", &mustfree);
+	if (s != NULL)
+	{
+	    coll_path = scheme_make_path(s);
+	    MZ_GC_CHECK();
+	    if (mustfree)
+		vim_free(s);
+	}
+#  ifdef MZSCHEME_COLLECTS
+	if (coll_path == NULL)
+	{
+	    coll_path = scheme_make_path(MZSCHEME_COLLECTS);
+	    MZ_GC_CHECK();
+	}
 #  endif
+	if (coll_path != NULL)
+	{
+	    scheme_set_collects_path(coll_path);
+	    MZ_GC_CHECK();
+	}
+	MZ_GC_UNREG();
+    }
 # else
+#  ifdef MZSCHEME_COLLECTS
     {
 	Scheme_Object	*coll_string = NULL;
 	Scheme_Object	*coll_pair = NULL;
@@ -1045,6 +1130,71 @@
     }
 # endif
 #endif
+
+# if MZSCHEME_VERSION_MAJOR >= 600
+    {
+	Scheme_Object *config_path = NULL;
+	int mustfree = FALSE;
+	char_u *s;
+
+	MZ_GC_DECL_REG(1);
+	MZ_GC_VAR_IN_REG(0, config_path);
+	MZ_GC_REG();
+	/* workaround for dynamic loading on windows */
+	s = vim_getenv("PLTCONFIGDIR", &mustfree);
+	if (s != NULL)
+	{
+	    config_path = scheme_make_path(s);
+	    MZ_GC_CHECK();
+	    if (mustfree)
+		vim_free(s);
+	}
+#ifdef MZSCHEME_CONFIGDIR
+	if (config_path == NULL)
+	{
+	    config_path = scheme_make_path(MZSCHEME_CONFIGDIR);
+	    MZ_GC_CHECK();
+	}
+#endif
+	if (config_path != NULL)
+	{
+	    scheme_set_config_path(config_path);
+	    MZ_GC_CHECK();
+	}
+	MZ_GC_UNREG();
+    }
+# endif
+
+#if MZSCHEME_VERSION_MAJOR >= 400
+    scheme_init_collection_paths(environment, scheme_null);
+#endif
+
+    /*
+     * versions 4.x do not provide Scheme bindings by default
+     * we need to add them explicitly
+     */
+    {
+	/* use error handler to avoid abort */
+	scheme_dynamic_wind(NULL, load_base_module, NULL,
+				    load_base_module_on_error, "racket/base");
+	if (load_base_module_failed)
+	{
+	    load_base_module_failed = FALSE;
+	    scheme_dynamic_wind(NULL, load_base_module, NULL,
+				    load_base_module_on_error, "scheme/base");
+	    if (load_base_module_failed)
+		return -1;
+	}
+    }
+
+    register_vim_exn();
+    /* use new environment to initialise exception handling */
+    init_exn_catching_apply();
+
+    /* redirect output */
+    scheme_console_output = do_output;
+    scheme_console_printf = do_printf;
+
 #ifdef HAVE_SANDBOX
     {
 	Scheme_Object	*make_security_guard = NULL;
@@ -1118,6 +1268,8 @@
      * whether thread scheduling is (or not) required
      */
     scheme_notify_multithread = notify_multithread;
+
+    return 0;
 }
 
 /*
@@ -1130,13 +1282,17 @@
     if (!initialized)
     {
 #ifdef DYNAMIC_MZSCHEME
-	if (!mzscheme_enabled(TRUE))
+	if (disabled || !mzscheme_enabled(TRUE))
 	{
 	    EMSG(_("E815: Sorry, this command is disabled, the MzScheme libraries could not be loaded."));
 	    return -1;
 	}
 #endif
-	startup_mzscheme();
+	if (load_base_module_failed || startup_mzscheme())
+	{
+	    EMSG(_("Exxx: Sorry, this command is disabled, the MzScheme's racket/base module could not be loaded."));
+	    return -1;
+	}
 	initialized = TRUE;
     }
     {
diff --git a/src/version.c b/src/version.c
index 72c4497..baecfc7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1104,
+/**/
     1103,
 /**/
     1102,