Can I set up PVM in such way that master doesn't start own tasks?

Question

We have a Perceus cluster (Warewulf) consisting of 4-core master and a number of 4-core nodes. I can start PVM on the master and then add all nodes - it works fine. However, there are other guys who need this master for their tasks, so I cannot overload it. I have tried to start PVM on a node, but something goes wrong. First of all, PVM console doesn't start correctly - it always freezes the first time I run pvm command. Then I cannot add other nodes

libpvm [t40005]: pvm_addhosts(): Already in progress

But it is not true - I cleaned carefully /tmp/ and killed all pvm* processes left from previous attempts.

So now I have the only way - to run from the master. Therefore I need to set it in such way, that it will not run own tasks, but start tasks on the nodes.

Can you help me with this?

Or may be you know a better place to ask this question?