Thanks for your hint Wolfgang! I tried to put the persitence.xml everywhere in the war file without success. WEB-INF/persistence.xml WEB-INF/META-INF/persistence.xml WEB-INF/classes/persistence.xml WEB-INF/classes/META-INF/persistence.xml Maybe i also should have posted my persistence.xml: | <persistence> | <persistence-unit name="MyUnit"> | <jta-data-source>java:/MySqlDS</jta-data-source> | <properties> | <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect"/> | <property name="hibernate.hbm2ddl.auto" value="create-drop"/> | <property name="jboss.entity.manager.jndi.name" value="java:/MyUnit"/> | <property name="jboss.entity.manager.factory.jndi.name" value="java:/MyUnitFactory"/> | </properties> | </persistence-unit> | </persistence> | tried it with and without the jndi properties. :/ View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4097705#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...