--- a/mercurial/hg.py	Fri Oct 26 13:20:44 2012 +0200
+++ b/mercurial/hg.py	Fri Oct 26 14:37:03 2012 +0200
@@ -418,6 +418,7 @@
                 if uprev is None:
                     try:
                         uprev = destrepo._bookmarks['@']
+                        update = '@'
                     except KeyError:
                         try:
                             uprev = destrepo.branchtip('default')