[Plugin: Contact Form 7] Using PHP in Forms

Is there any way to use PHP variables in the contact form? We are building an affiliate site and want the contact requests to be sent to the affiliate whose page the visitor is on.

There are cookies set with the username and affiliate email, but when I echo the email using PHP, the form generates an error saying to contact the administrator.

http://wordpress.org/extend/plugins/contact-form-7/