diff -r 6c05b5e5c1be src/Makefile
--- a/src/Makefile	Wed Oct 20 21:23:33 2010 +0200
+++ b/src/Makefile	Thu Oct 21 13:27:46 2010 -0400
@@ -1321,7 +1321,7 @@
 .SUFFIXES: .c .o .pro
 
 PRE_DEFS = -Iproto $(DEFS) $(GUI_DEFS) $(GUI_IPATH) $(CPPFLAGS) $(EXTRA_IPATHS)
-POST_DEFS = $(X_CFLAGS) $(MZSCHEME_CFLAGS) $(TCL_CFLAGS) $(RUBY_CFLAGS) $(EXTRA_DEFS)
+POST_DEFS = $(X_CFLAGS) $(MZSCHEME_CFLAGS) $(TCL_CFLAGS) $(EXTRA_DEFS)
 
 ALL_CFLAGS = $(PRE_DEFS) $(CFLAGS) $(PROFILE_CFLAGS) $(POST_DEFS)
 
@@ -1329,7 +1329,7 @@
 # with "-E".
 OSDEF_CFLAGS = $(PRE_DEFS) $(POST_DEFS)
 
-LINT_CFLAGS = -DLINT -I. $(PRE_DEFS) $(POST_DEFS) $(LUA_CFLAGS) $(PERL_CFLAGS) $(PYTHON_CFLAGS) -Dinline= -D__extension__= -Dalloca=alloca
+LINT_CFLAGS = -DLINT -I. $(PRE_DEFS) $(POST_DEFS) $(RUBY_CFLAGS) $(LUA_CFLAGS) $(PERL_CFLAGS) $(PYTHON_CFLAGS) -Dinline= -D__extension__= -Dalloca=alloca
 
 LINT_EXTRA = -DUSE_SNIFF -DHANGUL_INPUT -D"__attribute__(x)="
 
@@ -2532,7 +2532,7 @@
 	$(CCC) $(PYTHON3_CFLAGS) $(PYTHON3_CFLAGS_EXTRA) -o $@ if_python3.c
 
 objects/if_ruby.o: if_ruby.c
-	$(CCC) -o $@ if_ruby.c
+	$(CCC) $(RUBY_CFLAGS) -o $@ if_ruby.c
 
 objects/if_sniff.o: if_sniff.c
 	$(CCC) -o $@ if_sniff.c
diff -r 6c05b5e5c1be src/config.h.in
--- a/src/config.h.in	Wed Oct 20 21:23:33 2010 +0200
+++ b/src/config.h.in	Thu Oct 21 13:27:46 2010 -0400
@@ -349,6 +349,9 @@
 /* Define if you want to include the Ruby interpreter. */
 #undef FEAT_RUBY
 
+/* Define for linking via dlopen() or LoadLibrary() */
+#undef DYNAMIC_RUBY
+
 /* Define if you want to include the Tcl interpreter. */
 #undef FEAT_TCL
 
diff -r 6c05b5e5c1be src/configure.in
--- a/src/configure.in	Wed Oct 20 21:23:33 2010 +0200
+++ b/src/configure.in	Thu Oct 21 13:27:46 2010 -0400
@@ -1299,10 +1299,10 @@
 
 AC_MSG_CHECKING(--enable-rubyinterp argument)
 AC_ARG_ENABLE(rubyinterp,
-	[  --enable-rubyinterp     Include Ruby interpreter.], ,
+	[  --enable-rubyinterp[=OPTS]     Include Ruby interpreter.  [default=no] [OPTS=no/yes/dynamic]], ,
 	[enable_rubyinterp="no"])
 AC_MSG_RESULT($enable_rubyinterp)
-if test "$enable_rubyinterp" = "yes"; then
+if test "$enable_rubyinterp" = "yes" -o "$enable_rubyinterp" = "dynamic"; then
   AC_MSG_CHECKING(--with-ruby-command argument)
   AC_ARG_WITH(ruby-command, [  --with-ruby-command=RUBY  name of the Ruby command (default: ruby)],
 	RUBY_CMD="$withval"; AC_MSG_RESULT($RUBY_CMD),
@@ -1360,6 +1360,12 @@
 	RUBY_OBJ="objects/if_ruby.o"
 	RUBY_PRO="if_ruby.pro"
 	AC_DEFINE(FEAT_RUBY)
+	if test "$enable_rubyinterp" = "dynamic"; then
+	  libruby=`$vi_cv_path_ruby -r rbconfig -e 'printf "lib%s.%s\n", Config::CONFIG[["RUBY_SO_NAME"]], Config::CONFIG[["DLEXT"]]'`
+	  AC_DEFINE(DYNAMIC_RUBY)
+	  RUBY_CFLAGS="-DDYNAMIC_RUBY_DLL=\\\"$libruby\\\" -DDYNAMIC_RUBY_VER=$rubyversion $RUBY_CFLAGS"
+	  RUBY_LIBS=
+	fi
       else
 	AC_MSG_RESULT(not found; disabling Ruby)
       fi
diff -r 6c05b5e5c1be src/if_ruby.c
--- a/src/if_ruby.c	Wed Oct 20 21:23:33 2010 +0200
+++ b/src/if_ruby.c	Thu Oct 21 13:27:46 2010 -0400
@@ -14,6 +14,8 @@
 #include <stdio.h>
 #include <string.h>
 
+#include "auto/config.h"
+
 #ifdef _WIN32
 # if !defined(DYNAMIC_RUBY_VER) || (DYNAMIC_RUBY_VER < 18)
 #   define NT
@@ -48,13 +50,15 @@
 #  define RUBY_EXPORT
 # endif
 
-#if !(defined(WIN32) || defined(_WIN64))
+#ifndef WIN3264
 # include <dlfcn.h>
-# define HANDLE void*
+# define HINSTANCE void*
+# define RUBY_PROC void*
 # define load_dll(n) dlopen((n), RTLD_LAZY|RTLD_GLOBAL)
 # define symbol_from_dll dlsym
 # define close_dll dlclose
 #else
+# define RUBY_PROC FARPROC
 # define load_dll LoadLibrary
 # define symbol_from_dll GetProcAddress
 # define close_dll FreeLibrary
@@ -174,7 +178,9 @@
 #define rb_lastline_get			dll_rb_lastline_get
 #define rb_lastline_set			dll_rb_lastline_set
 #define rb_load_protect			dll_rb_load_protect
+#ifndef RUBY19_OR_LATER
 #define rb_num2long			dll_rb_num2long
+#endif
 #define rb_num2ulong			dll_rb_num2ulong
 #define rb_obj_alloc			dll_rb_obj_alloc
 #define rb_obj_as_string		dll_rb_obj_as_string
@@ -186,6 +192,9 @@
 #ifdef rb_str_new2
 /* Ruby may #define rb_str_new2 to use rb_str_new_cstr. */
 # define need_rb_str_new_cstr 1
+/* Ruby's headers #define rb_str_new_cstr to make use of GCC's
+ * __builtin_constant_p extension. */
+# undef rb_str_new_cstr
 # define rb_str_new_cstr		dll_rb_str_new_cstr
 #else
 # define rb_str_new2			dll_rb_str_new2
@@ -206,9 +215,11 @@
 #endif
 #define ruby_init			dll_ruby_init
 #define ruby_init_loadpath		dll_ruby_init_loadpath
-#define NtInitialize			dll_NtInitialize
-#if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER >= 18
-# define rb_w32_snprintf		dll_rb_w32_snprintf
+#ifdef WIN3264
+# define NtInitialize			dll_NtInitialize
+# if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER >= 18
+#  define rb_w32_snprintf		dll_rb_w32_snprintf
+# endif
 #endif
 
 #ifdef RUBY19_OR_LATER
@@ -317,12 +328,11 @@
 }
 #endif
 
-static HINSTANCE hinstRuby = 0; /* Instance of ruby.dll */
+static HINSTANCE hinstRuby = NULL; /* Instance of ruby.dll */
 
 /*
  * Table of name to function pointer of ruby.
  */
-#define RUBY_PROC FARPROC
 static struct
 {
     char *name;
@@ -387,15 +397,17 @@
 #endif
     {"ruby_init", (RUBY_PROC*)&dll_ruby_init},
     {"ruby_init_loadpath", (RUBY_PROC*)&dll_ruby_init_loadpath},
+#ifdef WIN3264
     {
-#if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER < 19
+# if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER < 19
     "NtInitialize",
-#else
+# else
     "ruby_sysinit",
-#endif
+# endif
 			(RUBY_PROC*)&dll_NtInitialize},
-#if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER >= 18
+# if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER >= 18
     {"rb_w32_snprintf", (RUBY_PROC*)&dll_rb_w32_snprintf},
+# endif
 #endif
 #if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER >= 18
     {"rb_string_value_ptr", (RUBY_PROC*)&dll_rb_string_value_ptr},
@@ -424,7 +436,7 @@
     if (hinstRuby)
     {
 	close_dll(hinstRuby);
-	hinstRuby = 0;
+	hinstRuby = NULL;
     }
 }
 
@@ -454,7 +466,7 @@
 			ruby_funcname_table[i].name)))
 	{
 	    close_dll(hinstRuby);
-	    hinstRuby = 0;
+	    hinstRuby = NULL;
 	    if (verbose)
 		EMSG2(_(e_loadfunc), ruby_funcname_table[i].name);
 	    return FAIL;