diff --git a/ChangeLog b/ChangeLog
index f6bec84f5b..83b1e7c262 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Mon May 11 13:08:30 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* mkconfig.rb (rubylibdir): use rubylibprefix.  [ruby-dev:38426]
+
 Mon May 11 08:37:04 2009  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* ext/bigdecimal/bigdecimal.c (BigDecimal_coerce): support
diff --git a/mkconfig.rb b/mkconfig.rb
index 2a1ec927f2..393a1b9ef5 100755
--- a/mkconfig.rb
+++ b/mkconfig.rb
@@ -171,7 +171,7 @@ end
 print(*v_fast)
 print(*v_others)
 print <<EOS
-  CONFIG["rubylibdir"] = "$(libdir)/$(ruby_install_name)/$(ruby_version)"
+  CONFIG["rubylibdir"] = "$(rubylibprefix)/$(ruby_version)"
   CONFIG["archdir"] = "$(rubylibdir)/$(arch)"
   CONFIG["sitelibdir"] = "$(sitedir)/$(ruby_version)"
   CONFIG["sitearchdir"] = "$(sitelibdir)/$(sitearch)"