diff -r 848345a8d6ad -r 0c10cf819146 mercurial/cmdutil.py
--- a/mercurial/cmdutil.py	Thu Nov 29 16:37:15 2012 +0100
+++ b/mercurial/cmdutil.py	Fri Nov 30 00:43:55 2012 +0900
@@ -627,7 +627,7 @@
                 # subpath. The best we can do is to ignore it.
                 tempnode2 = None
             submatch = matchmod.narrowmatcher(subpath, match)
-            sub.diff(diffopts, tempnode2, submatch, changes=changes,
+            sub.diff(ui, diffopts, tempnode2, submatch, changes=changes,
                      stat=stat, fp=fp, prefix=prefix)
 
 class changeset_printer(object):