Susan Moskwa, a member of the Google Webmaster Central team, has said that afraid.org, a free DNS provider, has been known to block GoogleBot.
Just found out that your DNS provider (afraid.org) has been known to block Googlebot from certain sites. You're not the only one who's had this problem:http://www.ameir.net/blog/index.php?/archives/26-Site-removed-from-Google-due-to-FreeDNS.html
You may want to contact afraid.org about this.
This can be an issue with other DNS providers. So be careful when picking a DNS provider for your web server, it may make the difference between getting indexed by Google and other search engines or not getting indexed.
This discussion is actually a continuation of GoogleBot having DNS caching issues themselves.
Forum discussion at Google Groups.

Comments:
Josh
11/10/2007 11:28 pm
The google switch can be flipped on and off if you contact Josh. This was a unfortunate drastic measure that had to be done due to abuse of innocent domain owner's domains in Google. afraid.org did not kill the ability to allow Google access. The admin has added manual control over the process. If you go to http://freedns.afraid.org/subdomain/?g=1 you will see a blue "G" indicating whether or not a record is visible to Google (this is not documented anywhere). Josh