My understanding of java2ParentDelegation is to control the parent-first or parent-last behaviour. So if you have set java2ParentDelegation=true, then if the class is not already loaded, then it will always ask the parent first to load the class. And since in your case, the parent is capable of loading that class (from server/default/lib), it will always be loaded from the jars there. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4267826#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...