The Notification class is serializable, and hence any defined subclasses are too, unless they go out of their way not to be. But a notification may include referenced objects that are not serializable. In this case our current code will drop the notification instead of sending it to a remote client, which is acceptable, but may also drop other notifications that arrived at the same time, even if they were serializable. That's not good.

We need to code a unit test for this and revisit the notification-handling code. For JMXMP, the class ServerIntermediary contains a REVISIT comment indicating where it could be improved. For RMI, it is less clear how to resolve this problem.