Okay, I have been back through the changes and have found out what happened. This functionality was lost during a previous commit so I am creating a bug for it.
One of the design issues with support for stateful services was to be able to determine when to dispose of the StatefulSession. In the code I contributed I used message properties to tell the BusinessRulesProcessor to create the StatefulSession, continue to use it, or to dispose of it. In retrospect I am not sure this is necessarily a good design, as it requires the use of these message properties.
I don't believe these are currently working in ESB 4.6. I have been doing testing with ESB 4.6 and Drools 5 Complex Event Processing, and it appears the StatefulSession remains until the service is re-loaded (which is fine for the testing I have been doing).
I have written up other JIRAs recently proposing some ideas on how to better support CEP and StatefulSessions. One idea is to separate the management of the StatefulSession and the inserting of events into the StatefulSession into different services.
Thanks for the follow-up Jeff.
From what I can tell this has been broken since before ESB 4.4, which means that it also impacts all the SOA 4.3 releases.
While I think that we should reinstate this behaviour, as it is a necessary feature, I also agree that we should look at improving the way in which this is handled.