I don't know of any way to get an MDB to listen to a queue in a remote server. Is this
EJB 2.x or 3? Perhaps information/documentation about MDB configuration will give some hints as to if this can be done and how to do it.
The fun part, or course, is that you have to include the WLS messaging client JARs in with your EAR file containing the MDB. Then you get to resolve the version and duplicate class conflicts between those JARs and the JARs provided by JBoss AS.