diff -r 9df9444e96ec -r a348739da8f0 mercurial/commands.py
--- a/mercurial/commands.py	Mon Nov 28 01:18:15 2011 +0100
+++ b/mercurial/commands.py	Mon Nov 28 01:32:13 2011 +0100
@@ -5575,8 +5575,7 @@
         for fname in fnames:
             f = url.open(ui, fname)
             gen = changegroup.readbundle(f, fname)
-            modheads = repo.addchangegroup(gen, 'unbundle', 'bundle:' + fname,
-                                           lock=lock)
+            modheads = repo.addchangegroup(gen, 'unbundle', 'bundle:' + fname)
         bookmarks.updatecurrentbookmark(repo, wc.node(), wc.branch())
     finally:
         lock.release()