Customizing (extend) the Bell Mailer

[Elle]

I really am a fan of that simple php-script with Captcha! Never found anything that easy to set up!

I'd like to know if it's possible (and how) to extend the script with furter informations that would be sent with the mail.

Details:
I want to use it as an application form. Therefore I need an input-field for a date and another input-field for the course-title. Would be nice too if the applicant would leave his address (a phone number would be nice but not a must)

How would I customize the php-file to get it work that way?

[Gavin]

It is possible to customise if you have some basic knowledge of PHP, but there's no built in function that allows you to add extra fields without using PHP. The idea of the mailer is to be simple and easy to use for anyone that just wants an email form.