For some more contextual information: org.jboss.annotation.ejb.PoolClass in the 4.2.x series has been renamed/refactored as org.jboss.ejb3.annotation.Pool. (See http://wiki.jboss.org/wiki/Wiki.jsp?page=ToAS5.0.0.Beta3). For your installation, the following command (on *nix-based Systems) should return clean: shell> grep -R 'PoolClass' $JBOSS_HOME If this is not the case, your Beta3 install has some old configs copied into it, and is not clean. Assuming there are no references to PoolClass in your installation, I'd like to look further for you. S, ALR View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4115266#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...