Hi Ronald, thanks for your answer. The problem in JBPM 3 is that if you execute several instances of an application with embedded JBPM, you will receive optimistic lock exceptions in the timers and on asynchronous commands. We basically implemented a fix which implements some kind of "reservation" and distributes the timer handling onto the various application instances. Regards, Elisabeth View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4238505#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...