diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 42e1384..fdf2a41 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -921,6 +921,13 @@
     verify(L(3)*2 == 6)
     verify(L(3)*L(2) == 6)
 
+    # Test comparison of classes with dynamic metaclasses
+    class dynamicmetaclass(type):
+        __dynamic__ = 1
+    class someclass:
+        __metaclass__ = dynamicmetaclass
+    verify(someclass != object)
+
 def errors():
     if verbose: print "Testing errors..."
 
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 20c149e..027a568 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -2033,7 +2033,8 @@
 
 	if (!PyArg_ParseTuple(args, "O", &other))
 		return NULL;
-	if (!PyType_IsSubtype(other->ob_type, self->ob_type)) {
+	if (other->ob_type->tp_compare != func &&
+	    !PyType_IsSubtype(other->ob_type, self->ob_type)) {
 		PyErr_Format(
 			PyExc_TypeError,
 			"%s.__cmp__(x,y) requires y to be a '%s', not a '%s'",