diff --git a/gajim/groupchat_control.py b/gajim/groupchat_control.py
index 862082f34bb4c6fbe71c42c369726d0b12497cfd..587242161b72e414e5f56f94bb9a2029620853c6 100644
--- a/gajim/groupchat_control.py
+++ b/gajim/groupchat_control.py
@@ -1467,7 +1467,7 @@ def _on_destroyed(self, event):
         alternate = destroyed.alternate
         if alternate is not None:
             join_message = _('You can join this group chat '
-                             'instead: xmpp:%s?join') % alternate
+                             'instead: xmpp:%s?join') % str(alternate)
             self.add_info_message(join_message)
 
         self.got_disconnected()