Trying to separate an EAR into modules:

lib/persistent.jar <- includes the persistent units, references all jars including entities
module1.ejb.jar
module2.ejb.jar
...

if module1 contains both references to the PC (from session beans) and entities, deployment fails due to circular reference:

PC tries to gather entities from module1, but JBoss tries to resolve the PC refs from session beans while analysing the jar.

currently possible layout:

lib/persistent.jar
lib/module1-entities.jar
module1.jar