DNS Event log error 5509???

“The DNS server encountered an invalid DNS update message from 65.2.44.228. The packet was rejected. ”

65.2.44.228 is my Domain Controller and DNS Server

I’ve come across this one answer http://www.jsifaq.com/SUBG/TIP3400/rh3474.htm but, seing as my server is running win2k server SP3 it doesn’t apply.

the netbios and dns name of the server (and every computer in the domain for that matter) contain no special characters.

any ideas?