--- a/mercurial/sshrepo.py
+++ b/mercurial/sshrepo.py
@@ -134,7 +134,7 @@ class sshrepository(remoterepository):
         f = self.do_cmd("changegroup", roots=n)
         return self.pipei
 
-    def addchangegroup(self, cg):
+    def addchangegroup(self, cg, source):
         d = self.call("addchangegroup")
         if d:
             raise hg.RepoError(_("push refused: %s"), d)