There are however two cases I can think of where an message groups approach by itself is not sufficient to provide strict ordering. 1) ConnectionConsumer - this is not an issue in JBM 2.0 since there is no connection consumer, but it is an issue in JBM 1.4 2) XA transactions. Messages could be consumed in multiple transactions using the same consumer, and then rolled back in a different order to which they were consumed. To fix 2) we can use a message group but would also need to pin the group to the XA transaction preventing messages being consumed in any other XA transaction until it's committed/rolled back. This would also have to be persisted in storage with the prepared tx data, since if failure occurs after prepare and the server is restarted, delivery of messages for that message group cannot occur until the tx is resolved (rolled back/committed). View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4194620#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...