Firefox and Apache

Came across this frustrating fact, while trying to connect to Tomcat proxied behind Apache though an Ajax connection… and continuously getting “page not found”:

1. Firefox doesn’t pass the content-length header on POST requests.
2. Apache has a flag “SecFilterEngine” which if set to ‘On’ would tell Apache to reject requests without a content-length header.

Dilemma:

1. Shouldn’t Firefox send the content-length header?
2. Or, why should Apache demand it?

answers?