I am try to deploy a jar to an jboss server. It works on my environment. But when I deployed the same jar on another server, i kept getting an error saying that the persistence unit is already registered. There is no other bean using the same name and the same persistence unit name. I tried to restart the server and remove the tmp, work, data directory but still get the same error. here is my error:

ObjectName: jboss.j2ee:service=EJB3,module=wess_jpa.jar

State: FAILED

Reason: java.lang.RuntimeException: javax.management.InstanceAlreadyExistsException: persistence.units:unitName=dses_wess already registered.

This is almost identical to this issue in jboss forum but there is no solution: http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4211687#4211687