Hester - 10:55 pm on Jul 27, 2010 (gmt 0)
I get this:
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request GET /unicorn/.
Reason: Error reading from remote server
Apache/2 Server at validator.w3.org Port 80
Guess they've been slashdotted, or whatever the term is thesedays.