Some extra info on my previous post: In jbpm 3 we extended TaskInstance (hibernate level) with some property and used a custom TaskInstanceFactory. We could create a custom query to retrieve all tasks with a given value for that property (no need to use variables) + we could create a bi-directional mapping between the property object and the task object. But in jbpm 4 I don't see a possibility to do this, because we can't register a custom taskInstanceFactory. So we are forced (imho) to use a variable to bind a task to these objects in our datamodel (and loose the bi-directional mapping) or activily keep an extra mapping table up to date. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4249136#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...