The webmaster is a friend of mine, and I got this response from him.
- Andrew
----- Forwarded message from Blake Crosby <me@blakecrosby.com> -----
You will get an error 403 message if you meet the following criteria:
Your hostname's TLD contains anything BUT:
.com
.net
.org
.edu
.ca
If your IP address doesn't resolve, then you must belong to the following
groups of IP addresses:
24.0.0.0
209.0.0.0
162.53.0.0
66.38.0.0
198.163.0.0
There is no automatic way of finding out where you are coming from. I have
just been adding IP blocks as people tell me. If you give me the IP address
you are coming from, I will gladly add its block to the ACL.
Blake