The stacktrace is simply informing you that you didn't close the connection. What this means is that your FirebirdDS can be acquired from JNDI and you can open a connection. | <?xml version="1.0" encoding="UTF-8"?> | <persistence-unit name="order" transaction-type="JTA"> | <jta-data-source>java:/FIrebirdDS</jta-data-source> | </persistence-unit> | May have a typo. Is 'FIrebirdDS' what you intend, or should it be 'FirebirdDS'? Please post the full contents of your *-ds.xml file. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4008385#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...