How can we create a custom deployer to deploy EJB 3.0 ?

What i read is to use the concept of JMX with MBeans , i tried some examples on simple MBeans which are working fine. But the concepts of applying MBean to override the existing deployer or to write a custom deployer were not clear to me.

Please tell me what are the steps that i need to follow to create a custom deployer or provide me any related links on the above specifed.