4.0.4 Http session replication currently has a dependency on APIs in 1.2.4. 1.2.4 and 1.2.3 are not interoperable, so in order to allow JBAS 4.0.4 to interoperate with early 4.0.x versions, we need to ensure the session replication code can work with 1.2.3. We need to rework the 1.2.4 API calls so that instead of working through an MBean proxy to the cache, they make direct calls on the JMX server. This should be simple to do and won't require hacking up the code. This removes the binary dependency on the 1.2.4 version of the MBean interface. These calls all depend on the new "useMarshalling" attribute being true, and the code is designed to still work if the attribute is false, so a simple check of the attribute should suffice. If the attribute check fails because the attribute doesn't exist, that's the same as its being set to false.

Fine-grained replication also requires the presence of some config attributes in tc5-cluster-service.xml. Some of these attributes don't exist in 1.2.3. But, these can be grouped together in the file and commented, etc. to make it fairly easy to turn on and off.