Hi,
OK, so the problem is that using the PHP mail function and sendmail you can set the From: address in the contents of the email message but you can't on the envelope. The web server becomes the sender of the email which is why the MAIL FROM: in the envelope is being set to apache.
So I see two choices:
1) Don't use the built-in PHP mail functions in the script but rather use something like PHPMailer which is full featured email transfer class for PHP.
http://phpmailer.sourceforge.net/
2) Configure your machine correctly to have the right domain name (not localhost.local) and then forward all emails from the apache account to yourself using the .forward file.
I hope that helps,
THP