Is there any chance that your app contains hibernate libraries, which conflict with the ones of JBoss? This is suspicious: java.lang.ClassCastException: org.hibernate.ejb.HibernatePersistence cannot be cast to javax.persistence.spi.PersistenceProvider | ... | controller.usuariosC.<init>(usuariosC.java:29) | ... This cast should be possible, if the classloader is the same. What is "controller.usuariosC", and what does it look like? Wolfgang View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4218738#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...