diff --git a/ChangeLog b/ChangeLog
index 1e3c49ee84..54f3d52267 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Wed Aug 24 09:49:10 2011  Koichi Sasada  <ko1@atdot.net>
+
+	* insns.def (defined): fix to checking class variable.
+	  A patch by Magnus Holm <judofyr@gmail.com>.  Thanks!
+
+	* test/ruby/test_variable.rb: add a test for above.
+
 Wed Aug 24 08:53:06 2011  Eric Hodel  <drbrain@segment7.net>
 
 	* lib/rdoc:  Update to RDoc 3.9.3.  Fixes RDoc with `ruby -Ku`.  Allows
diff --git a/insns.def b/insns.def
index 829918c117..0541b344f9 100644
--- a/insns.def
+++ b/insns.def
@@ -773,11 +773,14 @@ defined
 	}
 	break;
       case DEFINED_CVAR:
-	klass = vm_get_cbase(GET_ISEQ(), GET_LFP(), GET_DFP());
+	{
+	NODE *cref = vm_get_cref(GET_ISEQ(), GET_LFP(), GET_DFP());
+	klass = vm_get_cvar_base(cref);
 	if (rb_cvar_defined(klass, SYM2ID(obj))) {
 	    expr_type = "class variable";
 	}
 	break;
+	}
       case DEFINED_CONST:
 	klass = v;
 	if (vm_get_ev_const(th, GET_ISEQ(), klass, SYM2ID(obj), 1)) {
diff --git a/test/ruby/test_variable.rb b/test/ruby/test_variable.rb
index 53e00301dc..32b3d61573 100644
--- a/test/ruby/test_variable.rb
+++ b/test/ruby/test_variable.rb
@@ -55,6 +55,11 @@ class TestVariable < Test::Unit::TestCase
     assert_equal("Cronus", atlas.ruler0)
     assert_equal("Zeus", atlas.ruler3)
     assert_equal("Cronus", atlas.ruler4)
+    assert_nothing_raised do
+      class << Gods
+        defined?(@@rule) && @@rule
+      end
+    end
   end
 
   def test_local_variables