Better architecture to outsource resource-intensive work to another programm

I want to find a better architecture for sending commands to another programm which handles resource-intensive work.

Our current workflow

We have a JBoss Server (Java EE6 Jboss 7.1.3) which creates a command file for another programm. The other one is started with stdin parameters from the JBoss contex, which is reading the command file what to do. During the job the server gets messages that a certain item was handled. If the job is finished (e.g. create 300 Word documents with content, or calling webservices) the Server gets notified over RMI.

New requirements

The worker programm should now be placed on a different machine. Also the calling should be over tcp. It should be possible to have a few instances which will be working on different jobs (or even machines). This programm(s) must also be always running.

Are the any frameworks in java which supports this kind of workflow? How would you do it? Would you use RMI or Sockets?