Is this the same error that you started off with? I ask this because, in your first few posts you mention using JBoss AS 4.2.2. And after a few posts, you have logs from JBoss AS-5.1.0.
jboss.j2ee:ear=PaymentAdmin.ear,jar=AuthenticationBean.jar,name=AuthenticationBean,service=EJB3,VM
ID=4cbb36267847712f:-23e97a62:12820e1ed0c:-7ff9 + is already registered
How are you deploying your application? Looks like that bean is already deployed once.