Add test for SF #658106.  Will backport.
diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 5a1fcec..0f656c2 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -2625,6 +2625,10 @@
     cant(Int(), int)
     cant(True, int)
     cant(2, bool)
+    o = object()
+    cant(o, type(1))
+    cant(o, type(None))
+    del o
 
 def setdict():
     if verbose: print "Testing __dict__ assignment..."