I don't know off hand, but that's an attack routine to exploit a buffer-overflow condition on Microsoft IIS servers.
For a tricky little redirector (assuming you are running Apache, and not another webserver), check out:
https://www.unix.com/cybersecurity/1685-code-red-redirect.html?s=. Keep in mind that this does not really help the load on the site all that much, and there is no simple way to fix this, but it's certainly funny!
Also, check the logs to see what site is sending these requests. You MAY be able to contact each of them, and let them know they've got a case of Code Red. Send them here:
http://www.microsoft.com/technet/tre...s/codealrt.asp.
HAND