By definition a @Transient field will not get serialized/streamed. If you are using it as a lock to synchronise on, that lock would only be valid on a single JVM. Regarding the issue with JBoss Cache, Hibernate and JBoss Transactions, this is to do with Hibernate using a transaction manager outside of an app server. If you are using this combination within a Java EE app server you should be fine. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4102867#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...