The following error message should make a reference to spec EJB3 JPA 6.2.1.2:

20:39:08,015 INFO [PersistenceUnitDeployment] Starting persistence unit persistence.units:ear=jemos-ejb3-ear-1.0.0.ear,jar=jemos-ejb3-ejb-1.0.0.jar,unitName=jemos-ejb3-test-junit
20:39:08,031 WARN [ServiceController] Problem starting service persistence.units:ear=jemos-ejb3-ear-1.0.0.ear,jar=jemos-ejb3-ejb-1.0.0.jar,unitName=jemos-ejb3-test-junit
java.lang.RuntimeException: You have not defined a non-jta-data-source for a RESOURCE_LOCAL enabled persistence context named: jemos-ejb3-test-junit