Right, but in my tests, if you had different unit names then the entity beans couldn't have any relationships between them. The only solution I have found is like raja05 said, is to put the persistence.xml in a jar file in the ear file. And then reference from that persistence.xml file all the other jars. "grdzeli_kaci" wrote : hi all, i had already problem like this and my mistake was that i hadn't unitname in the persistance.xml file | i think if u must add this in u your persistance.xml | | | | <persistence-unit name="Blah1" transaction-type="JTA"> | | <jta-data-source>java:/XAOracleDS</jta-data-source> | | <class>com.magti.businesslayer.ejb3entity.oracle.Test</class> | | <properties> | | [props] | | </properties> | | </persistence-unit> | | | | | in second persistanc.xml | | | <persistence-unit name="Blah2" transaction-type="JTA"> | | <jta-data-source>java:/XAOracleDS</jta-data-source> | | <class>com.magti.businesslayer.ejb3entity.oracle.Test</class> | | <properties> | | [props] | | </properties> | | </persistence-unit> | | | | | | u also could put more then one persistance unit in one persistance.xml file | | | <persistence-unit name="Blah1" transaction-type="JTA"> | | <jta-data-source>java:/XAOracleDS</jta-data-source> | | <class>com.magti.businesslayer.ejb3entity.oracle.Test</class> | | <properties> | | [props] | | </properties> | | </persistence-unit> | | <persistence-unit name="Blah2" transaction-type="JTA"> | | <jta-data-source>java:/XAOracleDS</jta-data-source> | | <class>com.magti.businesslayer.ejb3entity.oracle.Test</class> | | <properties> | | [props] | | </properties> | | </persistence-unit> | | | | View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3965037#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...