Postfix and return path, spam problem

When I try to send email via Php mail() function, if the domain I send from is “” and email is “info@test.con”, as return path in header I get:”, where is the hostname of my vps.
So gmail put that email in spam folder.
How could I get mail() function sending email via postfix with return path: So gmail and similar doesn’t consider it as spam?
I’m using virtualmin gpl in centos 5.7 & 6.


<?php mail('', 'Subject', 'Body', 'From:', '-f'); ?>

-f = your solution, try it and let us know,