Apache redirects in case of http errors

We have a web application. The backend is an Apache Web Server (Version 2.2).

As described in the following document

http://ift.tt/210KulO

we have configured an ErrorDocument for 404 which redirects to a cgi program.

ErrorDocument 404 /cgi-bin/log_false_request.pl

In the program "log_false_request" we write the ip address, the user-agent and the original URL (request uri) of the request to a log file.

When an http error 500 happens and the request is a post, it would also be interesting to have the post body.

Does apache also redirect the response body in case of a post request?

Thanks alot in advance.