I talked to NAI and here's what I got from them. They do support their
product on a cluster. It is however not Yes Certified and won't be. They
provide 3 tids (listed below) to use to set this up. This is a summary
of what I think needs to be done. Any comments on this or advice is
appreciated, because I plan to test this out soon.

1.) Install locally on sys volume.
2.) Make sure activity log stays on sys volume.
3.) Set the scanner to "scan all volumes" so that it will Scan the
volumes mounted on the cluster.