You copy it to either server/all/deploy or server/default/deploy. If you don't know the difference between "all" or "default" then server/default/deploy is probably where you should copy it :-) Yes, pluggable-instrumentor.jar should go in the bin/ folder. The instructions are the same for AS 4.2.0 as for 4.0.x View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4049816#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...