Test case included, setting poolingFactory.setUseAnonymousProducers(false) allows the test to pass. If this isn't a bug, we may need to document why this behavior occurs.

Note: in the attached test, the blocked producer roughly correlates to a switch to paging mode in the attached test; it's unclear if the switch to paging mode switch is causal because you can increase the message size and the switch to paging mode does not correlate as well.