diff -r bb43a9abca80 -r a8cef95cea88 mercurial/subrepo.py
--- a/mercurial/subrepo.py	Fri Jan 07 17:44:23 2011 +0100
+++ b/mercurial/subrepo.py	Tue Jan 04 11:33:47 2011 -0600
@@ -544,7 +544,7 @@
 
     def dirty(self, ignoreupdate=False):
         if not self._wcchanged()[0]:
-            if self._wcrev() == self._state[1] and not ignoreupdate:
+            if self._wcrev() == self._state[1] or ignoreupdate:
                 return False
         return True