For a couple of days I can't access www.af.mil. It seems to have
vanished from DNS servers around the world. I somehow found an IP
address for it and the site is there and working. But the af.mil doesn't
resolve to an address. What is your experience?

Boyan

Problem is the DNS-server of your ISP. According to the DNS-server of your
source domain mail.bg, the domain is not known..

server ns.mail.bg
Default server: ns.mail.bg
Address: 193.201.172.98#53
www.af.mil
Server: ns.mail.bg
Address: 193.201.172.98#53

** server can't find www.af.mil: REFUSED

Please check with your ISP for this. They probably have to fix their
DNS'es..

Regards,

Nils Kolstein
http://www.xs4all.nl/~kolstein