This contact form uses a comprehensive PHP emailing class that will suit your needs. I designed it so you may modify all your settings in a single XML file including SMTP as well as standard mail. If your site requires more in-depth settings, such as disabling authentication, disabling HTML preview, using the 'sendmail' feature, etc... , you may adjust these in the mail.php file. Ideally, it is set to function in the most common way by either regular mail or SMTP. Enjoy.