1. The schema validation succeeds. Everytime a transaction comes in play the error occurs:-( 2. setting com.arjuna.ats.jta.allowMultipleLastResources to true and using two local-tx-datasource has helped for the moment. But after reading all the docs vickyk gently pointed, i do want to use xa datasources. For now i do not know why the exception occur. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4064886#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...