Every time another error ;-)?
Any chance that the ejb class gets deployed twice (e.g. in two locations of the EAR/JAR structure)?
You have "AuthenticationLocalHome" and "AuthenticationHome" files. Do you require them? Actually, the concept of "Home interfaces" is EJB 2.x, so you don't need them in EJB3.
If this (and upgrading to a more recent JDK) does not help, please post the relevant content of "ejb-jar.xml" and "jboss.xml".
Best regards
Wolfgang