JMX is the technology behind the modular architectures of Apache Geronimo and JBoss. MX4J founder, Simone Bordet once belonged to the JBoss project and is now an Apache Geronimo committer.
I won't go too far into technical details, but the JMX Remoting specification (JSR 160) has been successfully implemented by the MX4J team. JMX Remoting will extend the benefits of JMX over the network, clearing the way for a new generation of clustered Open Source application servers, web service frameworks and the like.
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