This is using build 10183.

Messages that have been rolled back are redelivered out of sequence.

For example, we publish 5 messages to a Q with message body 1,2,3,4,5 respectively.
Create a transacted session and consume all 5 messages. Do not commit or rollback. Simply close the consumer and the session. This should cause an implicit rollback.
Then create a new consumer and consume the same messages. You expect the messages to be delivered in the same order, 1,2,3,4,5.
As the results show, the sequence in which the 5 messages are redelivered is quite random. The attached log file, results.txt shows the output from the test client for 3 separate runs. In each of the three runs, the redelivered messages are in some random sequence.

We are using a 0 client side buffer (<consumer-window-size>0</consumer-window-size>).

Attached:
Test client
Results