--- a/mercurial/url.py	Fri May 08 15:14:04 2009 +0200
+++ b/mercurial/url.py	Mon May 11 07:55:13 2009 +0200
@@ -108,7 +108,8 @@
             self._writedebug(user, passwd)
             return (user, passwd)
 
-        user, passwd = self._readauthtoken(authuri)
+        if not user:
+            user, passwd = self._readauthtoken(authuri)
         if not user or not passwd:
             if not self.ui.interactive():
                 raise util.Abort(_('http authorization required'))