=== modified file 'mailman/client/_client.py'
--- mailman/client/_client.py	2011-10-31 22:42:40 +0000
+++ mailman/client/_client.py	2011-11-14 14:07:48 +0000
@@ -205,7 +205,9 @@
                 # in Mailman3Alpha8
                 if domain.base_url == web_host:
                     return domain
-            return []
+                    break
+            else:
+                return None
 
     def get_user(self, address):
         response, content = self._connection.call(