One of the reasons I'm going on about all this, is that messaging now (or very shortly) supports prefetching of messages (which incidentally gives us a massive boost in throughput :) ), so when I rollback a session, if I have to nack the messages delivered, I also have to nack all the prefetched ones on the client back to the server - which i want to avoid doing If I can avoid it, otherwise the order is going to be screwed when the nacked ones are redelivered (the prefetched ones will have jumped ahead). If I can deal with rollback locally (I.e. not nack the messages) I can just re-insert the delivered messages at the front of the prefetched messages on the client side and everything is much easier (and more performant - although performance for rollback is probably not an important issue) View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3958150#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...