Speaking of RPC,

I was just reading the FAQ of Port Monster and here's they're pitch on a RPC vulnerablility:

http://www.portmonster.com/index.php?d=help-faq#nt4

Can Port Monster help my NT 4 Workstation / Server and the RPC vulnerability that Microsoft won't patch?

Recently, Microsoft released information about a vulnerability in many versions on the Windows Operating System, in the RPC Service. This includes Windows XP, 2000, and NT 4. They have released patches for Windows XP, and 2000, but claim that due to "Architectural Limitations" they cannot create a patch for Windows NT 4 (This would be Workstation and Server). The suggested solution is to upgrade, or to simply block all traffic to port 135, which is the port that RPC uses. Here is where Port Monster can work for you. Port Monster can run on your Windows NT 4 machine, and you can block all traffic that attempts to access port 135, in fact, this is already done by default! There are several local ports that are protected by default, and port 135 is one of them. Therefore, yes indeed Port Monster can help you with this situation.

cheers