This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
JMX isn't a black magic monitoring system that can monitor anything -- it is more of a framework that enables you to monitor anything.
To be able to monitor the thing that you want, there has to be a mechanism (an API) that can be use to fetch the monitor data. There has to be an MBean that will use that API and monitor the thing. And finally, as a client, you have to instantiate and use the MBean, as it is supposed to be used.