The incorrect content length problem with Apache, how to stop waiting for data, and send a reply in CGI?

Hello

Maybe someone who knows apache internals can help on this issue.

We created an http client application, and a server CGI script on C++
to exchange data between the application which is spread among many
users and our server. Unfortunately the client application had a bug
with https POST method when it sent less data than specified in content
length header. It happens on a certain combination of input data
entered by end user. As the result the Apache server waits for the
missing data because of incorrect content length sent by the client,
and we never have a chance to send a reply back to the client
application. The client application simply closes the connection after
one minute timeout period.

Is there any way to force Apache to cancel this wait on receiving the
missing data in Post method and switch it to sending data to reply back
to the client application from CGI script?

We tried writing to stdout and/or closing stdin, but it doesn't help,
it seems Apache keeps on waiting, and doesn't want to send anything
while waiting for missing data because of incorrect content length.

Thanks,
Sam Kipers