Critical Description
Nulling the MessageReference handle on the Message during QueueEntry disposal can result in NPE in various places throughout the broker, when attempts from seperate areas of the broker to retrieve details that are held only in the Message overlap the reference update and encounter unexpected NPE's. The reference nulling should be removed until this can be accounted for. (It is no longer as necessary as it once was, thanks to more aggressive QueueEntry scavenging in the QueueEntryList)