I think your have the wrong class name. Try org/jboss /resource/adapter/jdbc/vendor/OracleXAExceptionFormatter.class View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4189543#4189543 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4189543