JBPM-3862

change :
    <property name="hibernate.id.new_generator_mappings" value="false" />
to :
 <!-- BZ 841786: AS7/EAP 6/Hib 4 uses new (sequence) generators which seem to cause problems -->
      <property name="hibernate.id.new_generator_mappings" value="true" />
and also change :
     <property name="hibernate.transaction.jta.platform" value="org.hibernate.service.jta.platform.internal.JBossAppServerJtaPlatform" />
to :
     <property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.JBossTransactionManagerLookup" />