Mail alias - PHP User

Hi,

I am using a mail alias in Virtualmin to pipe emails to a PHP script, (php -q /path/to/script.php) this all works great except for one little hitch. When somebody sends in an email with an attachment the script grabs that attachment and saves it to a directory for use by the website later.

The problem is when the script runs the user it runs as is 'nobody' does anybody happen to know if there is a simple way to run this under the same user as the website to prevent permission problems?

Any ideas / advice would be very much appreciated.

Thanks