deliveringCount.decrement is being called twice. I did some debugging and deliveringCount become negative at acknowledgeInternal. (I added some System.out to debug it) protected void acknowledgeInternal(Delivery d, Transaction tx, boolean persist) throws Exception | { | | .... | if (!d.isRecovered()) | { | if (deliveringCount.decrement() < 0) | { | System.out.println("Oops... deliveringCount became negative at acknowledgeInternal"); // I added this print here | } | } | | ...... | } | Why the test is asserting for -1? it seems to me the valid condition would be 0, and deliveringCount being decremented to -1 would be a bug? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4197471#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...