diff --git a/ChangeLog b/ChangeLog
index 9453b52f23..49e1a45488 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Mon May  5 23:49:40 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* insns.def (defineclass): was using wrong variable.  [ruby-dev:34592]
+
 Mon May  5 20:07:59 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* io.c (io_fflush): IO#flush problem within threads.  a patch from
diff --git a/insns.def b/insns.def
index 69849ff41e..ba7beec33c 100644
--- a/insns.def
+++ b/insns.def
@@ -931,7 +931,7 @@ defineclass
 
 	if (cbase == Qundef) {
 	    cbase = vm_get_cbase(th);
-	    if (NIL_P(klass)) {
+	    if (NIL_P(cbase)) {
 		rb_raise(rb_eTypeError, "no class/module to define constant");
 	    }
 	}