--- a/mercurial/localrepo.py	Mon Dec 17 17:00:24 2012 +0100
+++ b/mercurial/localrepo.py	Mon Dec 10 18:12:41 2012 +0100
@@ -2107,8 +2107,8 @@
         """
         cl = self.changelog
         if common:
-            nm = cl.nodemap
-            common = [n for n in common if n in nm]
+            hasnode = cl.hasnode
+            common = [n for n in common if hasnode(n)]
         else:
             common = [nullid]
         if not heads: