Okay, I solve it. The problem was that I programmatically added another MBean from the MBean contained and registered along with the SAR-File I used the following code: MBeanServer mbs = ManagementFactory.getPlatformMBeanServer(); | MyNewMBeanObject status = new MyNewMBeanObject(); | mbs.registerMBean(status, oName); So far so good, the added MBean can access all classes but no LoginModules (via LoginContext). Apparently JBoss does not like it, when you add an MBean programmtically and access JAAS from it. MBeans registered by JBoss via SAR-Files can access LoginModules just fine. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4144872#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...