nginx behind mod_proxy giving 408

[ajassal]

As part of rolling out nginx across our site, we are doing a phased
roll-out of services currently running behind apache (mod_proxy). 

For our first service we have nginx running behind apache (mod_proxy)
for some URLs. 
This is causing issues for certain POST requests where status returned
is 408 in nginx and lines such as

[Mon Sep 20 14:31:55 2010] [error] [client xxx] proxy: Error reading
from remote server returned by /xxxx
[Mon Sep 20 14:32:01 2010] [error] [client xxx] (70014)End of file
found: proxy: error reading status line from remote server xxx

appear in apache error log.

Increasing client_body_timeout does not an impact.

Comments?

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,132397,132397#msg-132397