diff --git a/ChangeLog b/ChangeLog
index 24363fe6d5..728bc7a250 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Sat Sep 29 10:12:20 2007  Tanaka Akira  <akr@fsij.org>
+
+	* variable.c (rb_ivar_set): fix class instance variable.
+
+	* object.c (rb_class_real): cl argument may be 0.
+
 Sat Sep 29 09:12:02 2007  Tanaka Akira  <akr@fsij.org>
 
 	* object.c (rb_class_real): use BUILTIN_TYPE instead of TYPE.
diff --git a/object.c b/object.c
index a6ded56724..031d2afdc8 100644
--- a/object.c
+++ b/object.c
@@ -99,6 +99,8 @@ rb_obj_equal(VALUE obj1, VALUE obj2)
 VALUE
 rb_class_real(VALUE cl)
 {
+    if (cl == 0)
+        return 0;
     while ((RBASIC(cl)->flags & FL_SINGLETON) || BUILTIN_TYPE(cl) == T_ICLASS) {
 	cl = RCLASS_SUPER(cl);
     }
diff --git a/variable.c b/variable.c
index d5c3bfe100..16859c2cab 100644
--- a/variable.c
+++ b/variable.c
@@ -1027,6 +1027,7 @@ rb_ivar_set(VALUE obj, ID id, VALUE val)
       case T_MODULE:
 	if (!RCLASS_IV_TBL(obj)) RCLASS_IV_TBL(obj) = st_init_numtable();
 	st_insert(RCLASS_IV_TBL(obj), id, val);
+        break;
       default:
 	generic_ivar_set(obj, id, val);
 	break;