JBoss development, A new author comment was created on the document PicketBox Authentication: http://community.jboss.org/docs/DOC-14745#comment-2858 Author : ANIL SALDHANA Profile: http://community.jboss.org/people/anil.saldhana@jboss.com Comment: Matt, thanks for the comment.  I think I made it as a string because that is what I have to set in the JDK JAAS config.  But thinking a bit, I think you are right, making it into a class would give the safety to developers (and avoid the CNFE). So if I take in a Class, I will need to still use its fqn in the background but that is ok. I will make the changes and release Beta3 on Monday.