PHP Bug Fix

I have bought a flash template for my website. One of the tabs is a contact page which holds an email form. When the form is completed and the 'send' button is pressed, an error dialogue is displayed - even though the form does email properly. My hosting provider (fasthosts.com) says it's a problem with the contact.php but not being a programmer I can't spot the problem. A friend has tested the template with his web host and it works perfectly. Fastshosts do specficy certain requirements for php (including a fifth '-f' parameter) but I'm not familiar with php so do understand what I'm missing. Estimates for fixing, please? Thanks