Hi Tom, good points... The Use case is the following: If I open one task (for me in Swing, but is is the same in Webapps too) I call the task, so that no other user starts the task concurrently. If now a user just closes the Form (which can be handled easly in Swing, maybe in JSF too) I undo the start, so that the Task is again in the pool. So my intention was really only to have it back in the actor pool and set the start date to null. In our apps, we never change variables between start and end of a task. But If we would do so, and the users closes the Form, maybe a real Undo like you proposed is the better choice, yes. Is that Undo ready in jbpm 3.2? Then I can switch my Command to that logic and we remove the undoStart method again, no problem. Or we remove the method and introduce a setter for date, then I can move the logic to the Special command and explain the intetntion there... EWhat do you think? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4018782#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...