If you start JBoss with Java SE 6 and try to connect to JBoss with JConsole you will get an internal JBoss error (ClassNotFoundException), the connect process will be also interrupted. In case you initialize the MBeanServer manually inside the EJBContainer (with EJB's @PostConstruct or in an interceptor) with e.g.: ManagementFactory.getPlatformMBeanServer() and then connect with JConsole - everything works well. In this case the registered MBean will appear in the JConsole, but not in the jmx-console (e.g. http://localhost:8080/jmx-console).
However, the JBoss proprietary way with the @org.jboss.annotation.ejb.Service, @org.jboss.annotation.ejb.Management annotations works well without any problems.
NEW: Online Workhop Effective WebApps without Frameworks is also coming to: MUC Airport.