It looks like the current SAR deployment code (jboss-as-sar) will deploy simple MBeans just fine. However, users may expect to be able to deploy older ServiceMBeans from previous Jboss AS versions. Currently, attempting to do this results in a ClassNotFoundException, since the org.jboss.system.ServiceMBean interface doesn't exist anymore.

Ideally this would also involve supporting ServiceMBeans that extend org.jboss.system.ServiceMBeanSupport, which also doesn't exist anymore.