diff --git a/ChangeLog b/ChangeLog
index 21bf2241d4..e8799ad420 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Wed Aug 12 15:52:04 2009  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* class.c (rb_define_module_id_under): fix the name.
+
+	* class.c (rb_define_module_under): fix for prevvious changes.
+
 Wed Aug 12 15:32:16 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* class.c (rb_define_class_id_under, rb_define_module_id_under):
diff --git a/class.c b/class.c
index 93b696798d..c64cbe72db 100644
--- a/class.c
+++ b/class.c
@@ -437,7 +437,7 @@ rb_define_module_under(VALUE outer, const char *name)
 }
 
 VALUE
-rb_define_module_under(VALUE outer, ID id)
+rb_define_module_id_under(VALUE outer, ID id)
 {
     VALUE module;
 
@@ -450,7 +450,7 @@ rb_define_module_under(VALUE outer, ID id)
     }
     module = rb_define_module_id(id);
     rb_const_set(outer, id, module);
-    rb_set_class_path(module, outer, name);
+    rb_set_class_path_string(module, outer, rb_id2str(id));
 
     return module;
 }