We are receiving duplicate messages when processing a moderate numbers of messages ( ~60,000 ), I have attached a JUNIT test which re-produces the issue on my machine with the broker configuration file used. Please note that It does take a few minutes to generate the test failure.
The test needs to be run with increased heap memory using the JMV option -Xmx512m
We initially found the issue using the IONA Fuse version 18.104.22.168 which would produce the same issue at 30,000 messages and without persistence storage. I later downloaded the ActiveMQ 5.1.0 version which would pass at 30,000 but fail at 60,000.
It is causing major issues for our project and hindering our application from going to production.