I believe it is the following property (in bold) in the peristence.xml file (from the booking example): <persistence> | <persistence-unit name="bookingDatabase"> | <provider>org.hibernate.ejb.HibernatePersistence</provider> | <jta-data-source>java:/bookingDatasource</jta-data-source> | <properties> | <property name="hibernate.hbm2ddl.auto" value="create-drop"/> | <property name="hibernate.show_sql" value="true"/> | <!-- These are the default for JBoss EJB3, but not for HEM: --> | <property name="hibernate.cache.provider_class" value="org.hibernate.cache.HashtableCacheProvider"/> | <property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.JBossTransactionManagerLookup"/> | </properties> | </persistence-unit> | </persistence> This actually bit me on butt when I first incorporated the seam setup into my existing project, as it dropped my tables and recreated them. Ouch - so mych for my test data! I learned that lesson pretty quickly. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3968454#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...