[Animats]

Another broken network device which takes it upon itself to mess with TCP connections passing through.

I ran into this a few years ago with Coyote Point load balancers. It turns out that if you send HTTP headers to a Coyote Point load balancer, and the last header field is "User-agent", and that field ends with "m" but does not otherwise contain "m", the connection does not go through the load balancer.

Complaining to Coyote Point produced typical clueless responses such as "Upgrade your software". (The problem wasn't at my end, but at sites with Coyote Point devices. Fortunately, I knew someone who had a Coyote Point unit, and we were able to force the situation there.) I had our system ("Sitetruth.com site rating system", note the "m") put an unnecessary "Accept" header field at the end of the header to work around the problem.

Coyote Point's filtering software is regular-expression based, and I suspect that somewhere, there is a rule with a "\m" instead of "\n".

A current issue: there are some sites where, if you make three HTTP requests for the same URL from the same IP address in a short period, further requests are ignored for about 15 seconds. You can make this happen with three "wget" requests. Try "wget http://bitcointalk.org" three times in quick succession. Amusingly, this limiter only applies for HTTP sessions, not HTTPS.