XP W2K3 W2K8 disabling UDP:69

I have a situation in which a PCI audit was conducted on our network. They found on several of our systems UDP:69 was found listening. We checked all of the machines that included XP,W2K3 server, W2K8 server and found that TFTP was not running as a service but only that the port was listening. I ran nmap against the ports and saw that they are in an open state. So I was asked to go around these system and disable these ports from listening. Some of these servers are Domain Controllers and most do not have firewalls running on them and are not permitted to have them enabled on them as well. So after reading several articles I was unable to disable UDP:69 using IPsec or going into c:\system32\drivers\etc\services like so forums have suggested.

http://www.windowsnetworking.com/ar...erver-2008-advanced-firewall-MMC-snap-in.html



http://support.microsoft.com/kb/813878



http://www.techrepublic.com/blog/ne...igurations-on-windows-server-2008-systems/481

Any suggestions ???