The lockMode = "FORCE". This is what the debugger says. I don't know where to look for in the database for the lock mode in the join table??? the parentToken that will be locked has a node attribute that called Fork !! The token that is referred to in the exception has a node reference to the Fork!!. I dont know anything about the interal working of JBPM, so I can't say whether this is normal or not?? Jan Will inverstigate your other suggestions tomorrow. I'll keep you posted. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4196585#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...