This page talks about using JBossCache over a multiplexed JGroups channel.  Note that you first need the JGroups Multiplexer set up and running in JBossAS.

Note that this is only possible in JBoss Cache 2.x.

• Comment out the ClusterConfig attribute in your JBoss Cache config file.

• Use the MultiplexerService and MultiplexerStack attribs to point JBoss Cache to the multiplexer service and the stack to use.

See the JBoss Cache User Guide for more details.