JBoss Session Management and JBossWS WebServices Examples

It took me long time to properly implement session management with EJB and WebServices using JBoss 4.2.x and JBossWS 2.0.x. Documentation is rare, and I often found myself digging through JBoss source code.
Hopefully, this article either helps you to succeed, or – even better – I can talk you out of it. Did you carefully consider alternatives? If not, do so first.
In my example, I want to allow two groups, Users and Administrators, to use different operations, either by accessing the EJB directly, or by using a WebService adapter. The database