As a desperation measure, I reiinstalled the jboss AS and then tried again. This time no errors, the difference I noticed is that the following class was being used for Query Translation : org.hibernate.hql.ast.ASTQueryTranslatorFactory instead of this one in my original post : org.hibernate.transaction.JTATransactionFactory I have no idea why the change occured, I am using the installer and believe I did everything the same - but obviously that must not be the case. So guess it's case closed. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4021345#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...