Hmmm.... Just re-looked at the stacktrace: at org.jboss.ejb3.test.proxy.common.container.SessionContainer.invoke(SessionContainer.java:188) anonymous wrote : I'm actually trying to figure out the best place for the following testcase I think i got an answer to this question. The SessionContainer infact is part of the proxy. So the testcase too can go there. I don't know why, so far, i have been thinking that the problem was in the ejb3-test module :) (probably the package org.jboss.ejb3.test confused me). View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4169194#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...