I have a little update: the ejb-30.jar is only javax.ejb.* and javax.persistence.* interfaces for ejb and persistence. Once I copied those from jboss seam the booking application which uses ejb-3 micro-container worked. It seems to be that for Resin it is enough to update the interfaces (I wish it was that simple though :S ). I still can;t figure out a way to override that jar file in case if I am not allow to 'mess' with resin/lib... View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3994061#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...