You can configure all Jmx Agents with a single agent called DefaultJmxSupportAgent that will register your Mule instance with the following agents -

• Rmi agent (if necessary) on rmi://localhost:1099
• Jmx Registration agent
• Remote Jmx access on service:jmx:rmi:///jndi/rmi://localhost:1099/server
• Jmx Notification agent used to receive Server notifications using Jmx Notifications
• Log4J Jmx Agent

Just add the following to your configuration -

<agent name="JMX" className="org.mule.management.agents.DefaultJmxSupportAgent"/>