No, its stuff that is implemented deep in the Seam lifecycle. Each ConversationEntry has a ReentrantLock. Well, the code itself is cluster safe, but unless you use session affinity, there is still no way to prevent concurrent requests on different machines. This could potentially cause data corruption. There is no way to solve this problem without destroying performance. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3985085#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...