--- a/mercurial/util.py	Sun Feb 03 19:29:05 2008 -0600
+++ b/mercurial/util.py	Sun Feb 03 19:29:05 2008 -0600
@@ -1086,6 +1086,9 @@
 else:
     nulldev = '/dev/null'
 
+    def lookup_reg(key, name=None, scope=None):
+        return None
+
     def rcfiles(path):
         rcs = [os.path.join(path, 'hgrc')]
         rcdir = os.path.join(path, 'hgrc.d')