I've just completed the integration test agains JBossAS 4.2.0.GA with JBossMQ which passes. I hade a similar exception to yours this morning and the problem was like Tom said, that I had an old jbossesb-rosetta.jar in jbossesb.sar/lib. I can run 'ant dist' without any error. Could you run 'ant clean dist' and see this if you are still getting this error? Thanks, Daniel View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4099326#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...