Thanks Michael, i have not found the thread i mentioned above. I explicitly refer to chapter 11.1.3. When i try to pass the var variable(fan) of a datatable to a method, then a null value is passed. This behaviour is consistent with seam docu(1.3.0Alpha)anonymous wrote : Note: You can not pass objects as arguments! All that is passed is names,[...] If the arguments can not be resolved at that time (because hotel and user variables can not be found in any available context) the action method will be called with null arguments! The var variable is not present in any scope, so null must be passed. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4055884#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...