diff --git a/ChangeLog b/ChangeLog
index 3b1f8147ec..f7ec6d727d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Apr  2 05:38:17 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* include/ruby/ruby.h (InitVM): calls per-VM initialization in
+	  single VM, but does nothing in MVM.
+
 Fri Apr  2 02:56:56 2010  Marc-Andre Lafortune  <ruby-core@marc-andre.ca>
 
 	* lib/matrix.rb: : New instance methods:
diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h
index 7b482ccb17..5c00c8d155 100644
--- a/include/ruby/ruby.h
+++ b/include/ruby/ruby.h
@@ -1401,6 +1401,8 @@ int st_strncasecmp(const char *s1, const char *s2, size_t n);
 unsigned long ruby_strtoul(const char *str, char **endptr, int base);
 #define STRTOUL(str, endptr, base) (ruby_strtoul(str, endptr, base))
 
+#define InitVM(ext) {void InitVM_##ext(void);InitVM_##ext();}
+
 #if defined(__cplusplus)
 #if 0
 { /* satisfy cc-mode */