Fix regression introduced in r1689.

git-svn-id: https://svn.erp5.org/repos/neo/trunk@1726 71dcc9de-d417-0410-9af5-da40c76e7ee4

neo/dispatcher.py

@@ -50,7 +50,7 @@ class Dispatcher:
     def pop(self, conn, msg_id, default=MARKER):
         """Retrieve register-time provided payload."""
         result = self.message_table.get(id(conn), EMPTY).pop(msg_id, default)
-        if default is MARKER:
+        if result is MARKER:
             raise KeyError, (id(conn), msg_id)
         return result