--- a/mercurial/fancyopts.py	Mon Jul 25 14:59:55 2011 -0500
+++ b/mercurial/fancyopts.py	Mon Jul 25 16:24:37 2011 -0500
@@ -75,7 +75,7 @@
         # copy defaults to state
         if isinstance(default, list):
             state[name] = default[:]
-        elif hasattr(default, '__call__'):
+        elif getattr(default, '__call__', False):
             state[name] = None
         else:
             state[name] = default