diff -r 5b41d5ad52bf -r d4d35fd0889d mercurial/commands.py
--- a/mercurial/commands.py	Sun Mar 04 17:12:12 2012 -0600
+++ b/mercurial/commands.py	Wed Mar 07 23:21:11 2012 +0000
@@ -4269,7 +4269,7 @@
         try:
             ret = hg.update(repo, checkout)
         except util.Abort, inst:
-            ui.warn(_("not updating: %s\n" % str(inst)))
+            ui.warn(_("not updating: %s\n") % str(inst))
             return 0
         if not ret and not checkout:
             if bookmarks.update(repo, [movemarkfrom], repo['.'].node()):