Tricky situation.. I think it may be due to DNS, but I haven't a clue where to start.

We have a simple contact form on our website that uses PHP Pear's Mail class to do secure authentication to our remote SMTP server.

The from address is a, we did that on purpose. So to reply to anyone that uses the form, we put the contact's email address as the "reply-to" address. However, when those emails do come in, the reply-to address is

Can anyone help? It's a VPS so I have full access to configuration files, etc.