I am using JBoss 4.0.5, my persistence.xml looks like this: | <persistence> | <persistence-unit name="system-entities"> | <jta-data-source>java:/SystemDB</jta-data-source> | <jar-file>../system-entities-1.0-SNAPSHOT.jar</jar-file> | <properties> | <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect"/> | <property name="hibernate.hbm2ddl.auto" value="update"/> | <property name="hibernate.show_sql" value="false"/> | <property name="hibernate.cache.provider_class" value="org.jboss.ejb3.entity.TreeCacheProviderHook"/> | <property name="hibernate.treecache.mbean.object_name" value="jboss.cache:service=EJB3EntityTreeCache"/> | <property name="entity.manager.factory.jndi.name" value="java:/system-entities"/> | </properties> | </persistence-unit> | </persistence> | Thanks for the link, it seems like exactly the same problem like mihai.ratiu has, the same server version and the same cache version. I also use flush as I need entities to be saved into dbs while processing between different entity managers. However, this other topic is unfinished, mihai.ratiu is asking, if it could be flush, nobody answered so far... Could I try to not use flush? Will not I work with inconsistent data then?? Thanks for your time. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4206126#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...