diff -r 4ca434500dbf -r 54f063acc5ea mercurial/cmdutil.py
--- a/mercurial/cmdutil.py	Mon Dec 03 13:17:01 2012 -0800
+++ b/mercurial/cmdutil.py	Tue Dec 04 11:19:32 2012 -0600
@@ -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):