--- a/mercurial/statichttprepo.py	Tue Jan 01 21:27:13 2013 +0100
+++ b/mercurial/statichttprepo.py	Mon Dec 24 03:21:15 2012 +0100
@@ -134,7 +134,7 @@
         self.changelog = changelog.changelog(self.sopener)
         self._tags = None
         self.nodetagscache = None
-        self._branchcache = None
+        self._branchcaches = {}
         self.encodepats = None
         self.decodepats = None