end-to-end disconnect notification?

[nginxuser100]

Hi, given 
client --(tcp)-->nginx --(fcgi)-->fcgi server --(tcp)--> back-end server
if the client initiates a TCP disconnect, is there a way for NGINX to carry
out the termination to the fcgi server?
Or if the back-end server disconnects, how can the fcgi server communicate
the disconnect all the way to nginx and the client?

>From what I observed, a client could send a TCP FIN, but NGINX will keep the
FCGX connection up.
Thank you.

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,257618,257618#msg-257618