--- a/mercurial/commands.py	Fri Jun 27 15:20:50 2014 -0700
+++ b/mercurial/commands.py	Sat Jun 28 13:02:44 2014 +0900
@@ -5322,6 +5322,7 @@
             write = self.ui.write
         write(_('listening at http://%s%s/%s (bound to %s:%d)\n') %
               (fqaddr, port, prefix, bindaddr, self.httpd.port))
+        self.ui.flush()  # avoid buffering of status message
 
     def run(self):
         self.httpd.serve_forever()