Thanks for your reply. Thanks for clearing up the confusion re. the entity clustering. A (simple) shared DB is no good for my application as it would be a single point of failure so it looks like a need to either use the DB replication or DB clustering. Thanks - I can look into that then. I've got the database replication setup now for my test application so I will investigate the query issue further now. Thanks again, Ian View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4034560#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...