These ports need to be forwarded through your firewall to the NAM IP for desktop messaging, i havent tried them for NVM manager...
1148, 3098, 3103, 3104, 135.
I had to use a packet grabber to find out...
http://www.analogx.com/contents/down...twork/pmon.htm is where i got the grabber from, but you will probably have to connect with a laptop directly to the nam using a cross over cable to see what ports it uses without seeing a lot of other traffic...
Hope that helps.