Im having the same issue with the same configuration: Seam 1.1.0 GA Built registration example with ant, deployed to JBoss AS 4.0.5. "When I leave the password field empty I get a message "Validation Error" as expected." This validation error comes from register.jspx. The input text boxes have the attribute required=true. If you remove it wou will have the same exception. It seems that the restrictions on User.java, that is @NotNull @Length(min=5, max=15) are the root cause. As the length of the field is less than 5, an exception is being thrown and no being caught. Hope this helps View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4002925#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...