--- a/mercurial/commands.py	Mon Apr 19 16:47:44 2010 -0500
+++ b/mercurial/commands.py	Mon Apr 12 19:33:25 2010 -0400
@@ -2160,6 +2160,7 @@
         df = util.matchdate(opts["date"])
 
     opts['branch'] += opts.get('only_branch')
+    opts['branch'] = [repo.lookupbranch(b) for b in opts['branch']]
 
     displayer = cmdutil.show_changeset(ui, repo, opts, True, matchfn)
     def prep(ctx, fns):