diff --git a/src/auto/configure b/src/auto/configure
index 69aec67..1b3b0c7 100755
--- a/src/auto/configure
+++ b/src/auto/configure
@@ -821,6 +821,7 @@
 enable_gui
 enable_gtk2_check
 enable_gnome_check
+enable_gtk3_check
 enable_motif_check
 enable_athena_check
 enable_nextaw_check
@@ -1481,9 +1482,10 @@
   --enable-hangulinput    Include Hangul input support.
   --enable-xim            Include XIM input support.
   --enable-fontset        Include X fontset output support.
-  --enable-gui=OPTS     X11 GUI default=auto OPTS=auto/no/gtk2/gnome2/motif/athena/neXtaw/photon/carbon
+  --enable-gui=OPTS     X11 GUI default=auto OPTS=auto/no/gtk2/gnome2/gtk3/motif/athena/neXtaw/photon/carbon
   --enable-gtk2-check     If auto-select GUI, check for GTK+ 2 default=yes
   --enable-gnome-check    If GTK GUI, check for GNOME default=no
+  --enable-gtk3-check     If auto-select GUI, check for GTK+ 3 default=yes
   --enable-motif-check    If auto-select GUI, check for Motif default=yes
   --enable-athena-check   If auto-select GUI, check for Athena default=yes
   --enable-nextaw-check   If auto-select GUI, check for neXtaw default=yes
@@ -4355,7 +4357,7 @@
 
 
     if test "x$CARBON" = "xyes"; then
-      if test -z "$with_x" -a "X$enable_gui" != Xmotif -a "X$enable_gui" != Xathena -a "X$enable_gui" != Xgtk2; then
+      if test -z "$with_x" -a "X$enable_gui" != Xmotif -a "X$enable_gui" != Xathena -a "X$enable_gui" != Xgtk2 -a "X$enable_gui" != Xgtk3; then
 	with_x=no
       fi
     fi
@@ -8606,6 +8608,9 @@
 $as_echo "GNOME 2.x GUI support" >&6; }
 		SKIP_GNOME=
 		SKIP_GTK2=;;
+    gtk3)	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: GTK+ 3.x GUI support" >&5
+$as_echo "GTK+ 3.x GUI support" >&6; }
+		SKIP_GTK3=;;
     motif)	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: Motif GUI support" >&5
 $as_echo "Motif GUI support" >&6; }
 		SKIP_MOTIF=;;
@@ -8657,6 +8662,23 @@
   fi
 fi
 
+if test "x$SKIP_GTK3" != "xYES" -a "$enable_gui_canon" != "gtk3"; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether or not to look for GTK+ 3" >&5
+$as_echo_n "checking whether or not to look for GTK+ 3... " >&6; }
+  # Check whether --enable-gtk3-check was given.
+if test "${enable_gtk3_check+set}" = set; then :
+  enableval=$enable_gtk3_check;
+else
+  enable_gtk3_check="yes"
+fi
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_gtk3_check" >&5
+$as_echo "$enable_gtk3_check" >&6; }
+  if test "x$enable_gtk3_check" = "xno"; then
+    SKIP_GTK3=YES
+  fi
+fi
+
 if test "x$SKIP_MOTIF" != "xYES" -a "$enable_gui_canon" != "motif"; then
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether or not to look for Motif" >&5
 $as_echo_n "checking whether or not to look for Motif... " >&6; }
@@ -8831,13 +8853,13 @@
 
   if test "X$GTK_CONFIG" != "Xno" -o "X$PKG_CONFIG" != "Xno"; then
   {
-    min_gtk_version=2.2.0
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GTK - version >= $min_gtk_version" >&5
-$as_echo_n "checking for GTK - version >= $min_gtk_version... " >&6; }
     no_gtk=""
     if (test "X$SKIP_GTK2" != "XYES" -a "X$PKG_CONFIG" != "Xno") \
 	  && $PKG_CONFIG --exists gtk+-2.0; then
     {
+      min_gtk_version=2.2.0
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GTK - version >= $min_gtk_version" >&5
+$as_echo_n "checking for GTK - version >= $min_gtk_version... " >&6; }
                         GTK_CFLAGS=`$PKG_CONFIG --cflags gtk+-2.0`
       GTK_LIBDIR=`$PKG_CONFIG --libs-only-L gtk+-2.0`
       GTK_LIBS=`$PKG_CONFIG --libs gtk+-2.0`
@@ -8848,6 +8870,23 @@
       gtk_micro_version=`$PKG_CONFIG --modversion gtk+-2.0 | \
 	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\3/'`
     }
+    elif (test "X$SKIP_GTK3" != "XYES" -a "X$PKG_CONFIG" != "Xno") \
+	  && $PKG_CONFIG --exists gtk+-3.0; then
+    {
+      min_gtk_version=2.2.0
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GTK - version >= $min_gtk_version" >&5
+$as_echo_n "checking for GTK - version >= $min_gtk_version... " >&6; }
+
+      GTK_CFLAGS=`$PKG_CONFIG --cflags gtk+-3.0`
+      GTK_LIBDIR=`$PKG_CONFIG --libs-only-L gtk+-3.0`
+      GTK_LIBS=`$PKG_CONFIG --libs gtk+-3.0`
+      gtk_major_version=`$PKG_CONFIG --modversion gtk+-3.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\1/'`
+      gtk_minor_version=`$PKG_CONFIG --modversion gtk+-3.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\2/'`
+      gtk_micro_version=`$PKG_CONFIG --modversion gtk+-3.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\3/'`
+    }
     else
       no_gtk=yes
     fi
@@ -8943,6 +8982,7 @@
   rm -f conf.gtktest
 
     if test "x$GTK_CFLAGS" != "x"; then
+      SKIP_GTK3=YES
       SKIP_ATHENA=YES
       SKIP_NEXTAW=YES
       SKIP_MOTIF=YES
@@ -9044,6 +9084,218 @@
   fi
 fi
 
+
+if test -z "$SKIP_GTK3"; then
+
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking --disable-gtktest argument" >&5
+$as_echo_n "checking --disable-gtktest argument... " >&6; }
+  # Check whether --enable-gtktest was given.
+if test "${enable_gtktest+set}" = set; then :
+  enableval=$enable_gtktest;
+else
+  enable_gtktest=yes
+fi
+
+  if test "x$enable_gtktest" = "xyes" ; then
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: gtk test enabled" >&5
+$as_echo "gtk test enabled" >&6; }
+  else
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: gtk test disabled" >&5
+$as_echo "gtk test disabled" >&6; }
+  fi
+
+  if test "X$PKG_CONFIG" = "X"; then
+    # Extract the first word of "pkg-config", so it can be a program name with args.
+set dummy pkg-config; ac_word=$2
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+$as_echo_n "checking for $ac_word... " >&6; }
+if ${ac_cv_path_PKG_CONFIG+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  case $PKG_CONFIG in
+  [\\/]* | ?:[\\/]*)
+  ac_cv_path_PKG_CONFIG="$PKG_CONFIG" # Let the user override the test with a path.
+  ;;
+  *)
+  as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  test -z "$as_dir" && as_dir=.
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+    ac_cv_path_PKG_CONFIG="$as_dir/$ac_word$ac_exec_ext"
+    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+  test -z "$ac_cv_path_PKG_CONFIG" && ac_cv_path_PKG_CONFIG="no"
+  ;;
+esac
+fi
+PKG_CONFIG=$ac_cv_path_PKG_CONFIG
+if test -n "$PKG_CONFIG"; then
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $PKG_CONFIG" >&5
+$as_echo "$PKG_CONFIG" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
+  fi
+
+  if test "x$PKG_CONFIG" != "xno"; then
+
+  if test "X$GTK_CONFIG" != "Xno" -o "X$PKG_CONFIG" != "Xno"; then
+  {
+    no_gtk=""
+    if (test "X$SKIP_GTK2" != "XYES" -a "X$PKG_CONFIG" != "Xno") \
+	  && $PKG_CONFIG --exists gtk+-2.0; then
+    {
+      min_gtk_version=3.0.0
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GTK - version >= $min_gtk_version" >&5
+$as_echo_n "checking for GTK - version >= $min_gtk_version... " >&6; }
+                        GTK_CFLAGS=`$PKG_CONFIG --cflags gtk+-2.0`
+      GTK_LIBDIR=`$PKG_CONFIG --libs-only-L gtk+-2.0`
+      GTK_LIBS=`$PKG_CONFIG --libs gtk+-2.0`
+      gtk_major_version=`$PKG_CONFIG --modversion gtk+-2.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\1/'`
+      gtk_minor_version=`$PKG_CONFIG --modversion gtk+-2.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\2/'`
+      gtk_micro_version=`$PKG_CONFIG --modversion gtk+-2.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\3/'`
+    }
+    elif (test "X$SKIP_GTK3" != "XYES" -a "X$PKG_CONFIG" != "Xno") \
+	  && $PKG_CONFIG --exists gtk+-3.0; then
+    {
+      min_gtk_version=3.0.0
+      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GTK - version >= $min_gtk_version" >&5
+$as_echo_n "checking for GTK - version >= $min_gtk_version... " >&6; }
+
+      GTK_CFLAGS=`$PKG_CONFIG --cflags gtk+-3.0`
+      GTK_LIBDIR=`$PKG_CONFIG --libs-only-L gtk+-3.0`
+      GTK_LIBS=`$PKG_CONFIG --libs gtk+-3.0`
+      gtk_major_version=`$PKG_CONFIG --modversion gtk+-3.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\1/'`
+      gtk_minor_version=`$PKG_CONFIG --modversion gtk+-3.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\2/'`
+      gtk_micro_version=`$PKG_CONFIG --modversion gtk+-3.0 | \
+	     sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\)/\3/'`
+    }
+    else
+      no_gtk=yes
+    fi
+
+    if test "x$enable_gtktest" = "xyes" -a "x$no_gtk" = "x"; then
+    {
+      ac_save_CFLAGS="$CFLAGS"
+      ac_save_LIBS="$LIBS"
+      CFLAGS="$CFLAGS $GTK_CFLAGS"
+      LIBS="$LIBS $GTK_LIBS"
+
+                        rm -f conf.gtktest
+      if test "$cross_compiling" = yes; then :
+  echo $ac_n "cross compiling; assumed OK... $ac_c"
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <gtk/gtk.h>
+#include <stdio.h>
+#if STDC_HEADERS
+# include <stdlib.h>
+# include <stddef.h>
+#endif
+
+int
+main ()
+{
+int major, minor, micro;
+char *tmp_version;
+
+system ("touch conf.gtktest");
+
+/* HP/UX 9 (%@#!) writes to sscanf strings */
+tmp_version = g_strdup("$min_gtk_version");
+if (sscanf(tmp_version, "%d.%d.%d", &major, &minor, &micro) != 3) {
+   printf("%s, bad version string\n", "$min_gtk_version");
+   exit(1);
+ }
+
+if ((gtk_major_version > major) ||
+    ((gtk_major_version == major) && (gtk_minor_version > minor)) ||
+    ((gtk_major_version == major) && (gtk_minor_version == minor) &&
+				     (gtk_micro_version >= micro)))
+{
+    return 0;
+}
+return 1;
+}
+
+_ACEOF
+if ac_fn_c_try_run "$LINENO"; then :
+
+else
+  no_gtk=yes
+fi
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
+  conftest.$ac_objext conftest.beam conftest.$ac_ext
+fi
+
+      CFLAGS="$ac_save_CFLAGS"
+      LIBS="$ac_save_LIBS"
+    }
+    fi
+    if test "x$no_gtk" = x ; then
+      if test "x$enable_gtktest" = "xyes"; then
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes; found version $gtk_major_version.$gtk_minor_version.$gtk_micro_version" >&5
+$as_echo "yes; found version $gtk_major_version.$gtk_minor_version.$gtk_micro_version" >&6; }
+      else
+	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: found version $gtk_major_version.$gtk_minor_version.$gtk_micro_version" >&5
+$as_echo "found version $gtk_major_version.$gtk_minor_version.$gtk_micro_version" >&6; }
+      fi
+      GUI_LIB_LOC="$GTK_LIBDIR"
+		 GTK_LIBNAME="$GTK_LIBS"
+		GUI_INC_LOC="$GTK_CFLAGS"
+    else
+    {
+      { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+      GTK_CFLAGS=""
+      GTK_LIBS=""
+      :
+    }
+    fi
+  }
+  else
+    GTK_CFLAGS=""
+    GTK_LIBS=""
+    :
+  fi
+
+
+  rm -f conf.gtktest
+
+    if test "x$GTK_CFLAGS" != "x"; then
+      SKIP_GTK2=YES
+      SKIP_GNOME=YES
+      SKIP_ATHENA=YES
+      SKIP_NEXTAW=YES
+      SKIP_MOTIF=YES
+      GUITYPE=GTK
+
+      $as_echo "#define HAVE_GTK_MULTIHEAD 1" >>confdefs.h
+
+      $as_echo "#define USE_GTK3 1" >>confdefs.h
+
+    fi
+  fi
+fi
+
 if test "x$GUITYPE" = "xGTK"; then
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking version of Gdk-Pixbuf" >&5
 $as_echo_n "checking version of Gdk-Pixbuf... " >&6; }
@@ -9546,7 +9798,7 @@
 fi
 
 
-if test -z "$SKIP_ATHENA" -o -z "$SKIP_NEXTAW" -o -z "$SKIP_MOTIF" -o -z "$SKIP_GTK2"; then
+if test -z "$SKIP_ATHENA" -o -z "$SKIP_NEXTAW" -o -z "$SKIP_MOTIF" -o -z "$SKIP_GTK2" -o -z "$SKIP_GTK3"; then
     cppflags_save=$CPPFLAGS
   CPPFLAGS="$CPPFLAGS $X_CFLAGS"
   for ac_header in X11/xpm.h X11/Sunkeysym.h