diff -r 94e91205d9b6 -r 0bf0045000b5 mercurial/hook.py
--- a/mercurial/hook.py	Tue May 12 10:03:36 2009 -0400
+++ b/mercurial/hook.py	Wed May 13 14:08:39 2009 +0200
@@ -21,7 +21,7 @@
 
     ui.note(_("calling hook %s: %s\n") % (hname, funcname))
     obj = funcname
-    if not callable(obj):
+    if not hasattr(obj, '__call__'):
         d = funcname.rfind('.')
         if d == -1:
             raise util.Abort(_('%s hook is invalid ("%s" not in '
@@ -44,7 +44,7 @@
             raise util.Abort(_('%s hook is invalid '
                                '("%s" is not defined)') %
                              (hname, funcname))
-        if not callable(obj):
+        if not hasattr(obj, '__call__'):
             raise util.Abort(_('%s hook is invalid '
                                '("%s" is not callable)') %
                              (hname, funcname))
@@ -74,7 +74,7 @@
 
     env = {}
     for k, v in args.iteritems():
-        if callable(v):
+        if hasattr(v, '__call__'):
             v = v()
         env['HG_' + k.upper()] = v
 
@@ -107,7 +107,7 @@
         for hname, cmd in ui.configitems('hooks'):
             if hname.split('.')[0] != name or not cmd:
                 continue
-            if callable(cmd):
+            if hasattr(cmd, '__call__'):
                 r = _pythonhook(ui, repo, name, hname, cmd, args, throw) or r
             elif cmd.startswith('python:'):
                 if cmd.count(':') == 2: