I suspect this would make sense to only implement for persistent messages, since duplicate detection would be an extra QoS over and above that provided by persistent messages. The sweeping is an interesting although you only really want to retain the ids, not the entire message or message reference so this could be wasteful in terms of storage. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3977207#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...