The reason I thought I needed a jboss-service.xml file is because I got the impression that it is needed to have pooling. In the jboss books example rar for a non-tx fs jca implementation it is there for this reason. My rar (if I'm allowed to use it) is new (jca 1.5 compliant). The rar itself deploys, no problem. Not sure how a ds should look like if I have no service.xml file but do want to have pooling... But I'll try to find out more... thanks for the response and help so far. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4270073#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...