What do you want to achive with NOT_SUPPORTED as a default? If you want to simply prevent flushing of the persistence context, a much better approach is a Seam-managed PC with FlushModeType.MANUAL. The EJB3 spec mixes these concerns together and ties flushing to transactions. This is a major issue with the spec that hopefully will be fixed in the next revision. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4064015#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...