My problem apparently has gone away too, yesterday, so far running fine on two servers. I happened to rearrange how two Seam components (both stateful with scope application) were interacting. (For completeness of record: I moved storing of some kind of "unique id" from the one executing on timer to its "manager" for robustness, and made them both inject each other instead of one way because I had to.) Now the problem is gone. I.e. the recurring super long log entries related to passivation and mentioning "java.lang.NoClassDefFoundError: org/jaxen/VariableContext" are gone. It may have been related to a system exception in its method blasting a stateful session bean into non-existence. Not sure. Point is, the problem went away when I cleaned up code. Point is, the log didn't point at the cause, at least not in a way recognizable to me, which might not be anyone's fault or fixable. Just something to remember for next time. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4035325#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...