You can use @PoolClass(value = org.jboss.ejb3.StrictMaxPool.class, maxSize = 1) on the MDB. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4025039#4025039 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4025039