If you are using the JPAKnowledgeService, you need to send you current EntityManager instance as a parameter. As you may know already, jBPM5 uses JPA for the persistence mechanism, so you will need to find out how to create a new EntityManager and inject your current hibernate session in it. If you are planning to do that there is no need to use JTA, because you will just have one Hibernate Session and no syncronization is needed.
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