It's not Seam validator. It is WTP JavaScript validator that complains about Richfaces.hideModalPanel function. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4212216#4212216 Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&p=4212216