First of all, thanks for the replies! I'm also not convinced that my problems are based on ajax configuration, since I removed them all from the xml's. If I change the delegate member accessibility to protected, the error goes away (There comes a different error for me though which I did not had the time yet to resolve). Maybe one of the developers could take a look at this, as it seams to me that the problem is the access modifier of the class member org.jboss.seam.web.Ajax4jsfFilter.delegate (which probably should'nt be private). Thanks again View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4069153#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...