I should clearify a bit.
I like to keep my entity beans separate from my business logic EJB. I also use the entity beans in other applications. I created a jar containing the entity beans and a persistence.xml file
To inject the PersitanceContext into a sessoin bean I used the line below.
Yes the "XXX" is just random.
I also had to put the entity.jar in a
<module/>section in the applicaton.xml file