Gasp, I cannot edit my message. Sorry, I will make a second one : A friend show me some features of Eclipse, and I manage to find that the problem seems to come from this codeline from findTimersByDueDate() into org.jbpm.db.SchedulerSession : Iterator iterator = session.getNamedQuery("SchedulerSession.findTimersByDueDate").iterate(); Should it come from an hibernate misconfiguration? Or worth, a damaged mysql schema. How can I test my mysql schema? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3999433#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...