--- a/mercurial/localrepo.py	Mon Dec 24 03:04:12 2012 +0100
+++ b/mercurial/localrepo.py	Mon Dec 24 03:05:02 2012 +0100
@@ -147,6 +147,7 @@
                                         'dotencode'))
     openerreqs = set(('revlogv1', 'generaldelta'))
     requirements = ['revlogv1']
+    filtername = None
 
     def _baserequirements(self, create):
         return self.requirements[:]