I am trying to integrate Hibernate with JBoss and MS SQL Server. I am using JPA APIs for the same. I am getting the following exception:

java.lang.IllegalArgumentException: Unknown entity: com.savvion.test.Department
at org.hibernate.ejb.AbstractEntityManagerImpl.find(AbstractEntityManagerImpl.java:193)
at com.savvion.commons.bps.jpa.JPAService.getByPK(JPAService.java:275)
at com.savvion.commons.bps.jpa.JPAService.get(JPAService.java:174)
at com.savvion.test.JPAClient.insert(JPAClient.java:18)

Caused by: org.hibernate.MappingException: Unknown entity: com.savvion.test.Department
at org.hibernate.impl.SessionFactoryImpl.getEntityPersister(SessionFactoryImpl.java:580)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:91)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:905)
at org.hibernate.impl.SessionImpl.get(SessionImpl.java:842)
at org.hibernate.impl.SessionImpl.get(SessionImpl.java:835)
at org.hibernate.ejb.AbstractEntityManagerImpl.find(AbstractEntityManagerImpl.java:182)


The persistence unit that I am using is:

<persistence-unit name="DefaultJTA" transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>jdbc/SBMCommonDBXA</jta-data-source>
<properties>
<property name="hibernate.archive.autodetection" value="class, hbm"/>
<property name="hibernate.transaction.manager_lookup_class"
value="org.hibernate.transaction.JBossTransactionManagerLookup"/>
<property name="hibernate.show_sql" value="true"/>
<property name="hibernate.connection.datasource" value="jdbc/SBMCommonDBXA"/>
<property name="hibernate.dialect"
value="org.hibernate.dialect.SQLServerDialect" />
<property name="hibernate.connection.driver_class"
value="com.savvion.jdbc.sqlserver.SQLServerDriver" />
<property name="hibernate.current_session_context_class" value="jta"/>
</properties>
</persistence-unit>


A couple of things I have verified / tried:
1. The entities that are used (present at the same level as the META-INF folder containing persistence.xml) do not have any hibernate specific annotations.
2. Tried listing the entity classes in persistence unit using <class>
3. Database connectivity using the same driver is successful - tested with another java client.
4. The persistence unit itself gets loaded without any issues.

Appreciate any help on this issue...

Thanks!

Devan.