we noticed mdbs w/transaction on don't work if the prefetch size is less than the number of sessions for the mdb. There's an error in calculating the prefetchExtension in afterCommit and there's no notification that it might be time to send more messages. Apparently if the prefetch size is large enough one of the earlier acks triggers delivery of the next batch.
There are also a bunch of synchronization errors in some classes...
Bug
Closed
Major
PrefetchSubscription may not wake up if messages delivered in transaction
