For the persistence.xlm, I was confused between jbpm-human-task-service and the example. I see you configure the persistence in the persistence.xml of the application. It is not my prefered solution because it makes me have multiple persistence units in the same persistence.xml and the web service removed this "problem". But it is not blocking of course.
Can I ask why are you still using jpa1? You don't deploy your test on jboss7?