Hello! In the case of the mail-box, why not push the functionallity of reacting to an email into the implementation of the mailbox? E.g. change the mailbox.addMessage() method and dynamically set up a reference to the mailbox when you startup the bean. In general, you could use an Adapter/Notifier pattern (with the additional advantage of being able to send one message too several mailboxes). Am I missing something there? Cheers , Georg View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4257766#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...