Hi I tried following the approach given in http://www.jroller.com/jgilbert01/entry/extending_the_hibernate_validatio... by using the @Expression framework detailed there . The validation happens but Seam proceeds to the after phase and then fails when it tries to persist the form . The solution is elegant since it takes care of both the UI approach and using an API approach but I did not find a way to stop seam from not going to the next phase if validation fails. For now I am using http://www.jboss.com/index.html?module=bb&op=viewtopic&t=120754&a... Hope this helps people who are searching for a similar solution Regards Hari View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4121473#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...