Linux (2.4.18 and 2.4.19, for me anyway) with apache versions 2.0.40 to 2.0.43 (that I've tested anyways) is broken with TCP_CORK and IPv6. Bizarrely v6 requests will work the first few times and then start failing, typically you just wont get a response from the server. Though strace shows that it did try to send one.
Anyway, disabling TCP_CORK fixes it and it works fine again, useful info for anyone running IPv6, because believe me, it took me all morning to figure out what the hell was going on. Might be worth adding a --disable-tcp-cork option to ./configure for convienence :-) -- Colm MacCárthaigh
