Hibernate Core 3 which is part of EAP 5 / EWS 1 was not able to auto scan entities within EAP 6, this is because EAP 6 has a new architecture and it is a JAVA EE 6 certificated Application Server (which has JPA 2), but Hibernate Core 3 is a JPA 1 provider. To workaround this, the entities must be explicated in persistence.xml. This JIRA fixed the issue and now Hibernate Core 3 is able to be used within EAP 6 to auto scan entities, but please note, this use case is not recommended, the default JPA provider (Hibernate Core 4) provides better performance and functionality, we only provide this for limit support and for migration purpose only.