The official JBoss / Red Hat line is that JBAS 4.2.0 is built using Java 5 since the enterprise app platform will only be supported when run using Java 5. This is not something under my control. However, in your case there may be a combination of jars we can use on the client side so you can run Java 1.4 on the client. I'll get back to you soon on this. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4051787#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...