diff --git a/src/os_unix.h b/src/os_unix.h
index 53b31f8..485e057 100644
--- a/src/os_unix.h
+++ b/src/os_unix.h
@@ -364,22 +364,26 @@
 
 #define DFLT_ERRORFILE		"errors.err"
 
-#ifdef VMS
-# define DFLT_RUNTIMEPATH      "sys$login:vimfiles,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,sys$login:vimfiles/after"
-# define CLEAN_RUNTIMEPATH      "$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after"
-#else
-# ifdef RUNTIME_GLOBAL
-#  ifdef RUNTIME_GLOBAL_AFTER
-#   define DFLT_RUNTIMEPATH	"~/.vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER ",~/.vim/after"
-#   define CLEAN_RUNTIMEPATH	RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER
-#  else
-#   define DFLT_RUNTIMEPATH	"~/.vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after,~/.vim/after"
-#   define CLEAN_RUNTIMEPATH	RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after"
-#  endif
+#ifndef DFLT_RUNTIMEPATH
+
+# ifdef VMS
+#  define DFLT_RUNTIMEPATH      "sys$login:vimfiles,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,sys$login:vimfiles/after"
+#  define CLEAN_RUNTIMEPATH      "$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after"
 # else
-#  define DFLT_RUNTIMEPATH	"~/.vim,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,~/.vim/after"
-#  define CLEAN_RUNTIMEPATH	"$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after"
+#  ifdef RUNTIME_GLOBAL
+#   ifdef RUNTIME_GLOBAL_AFTER
+#    define DFLT_RUNTIMEPATH	"~/.vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER ",~/.vim/after"
+#    define CLEAN_RUNTIMEPATH	RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL_AFTER
+#   else
+#    define DFLT_RUNTIMEPATH	"~/.vim," RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after,~/.vim/after"
+#    define CLEAN_RUNTIMEPATH	RUNTIME_GLOBAL ",$VIMRUNTIME," RUNTIME_GLOBAL "/after"
+#   endif
+#  else
+#   define DFLT_RUNTIMEPATH	"~/.vim,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,~/.vim/after"
+#   define CLEAN_RUNTIMEPATH	"$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after"
+#  endif
 # endif
+
 #endif
 
 #ifdef VMS