The following license came with and applies to the captcha security programme (CaptchaSecurityImages.php):

File: CaptchaSecurityImages.php
Author: Simon Jarvis
Copyright: 2006 Simon Jarvis
Date: 03/08/06
Updated: 07/02/07
Requirements: PHP 4/5 with GD and FreeType libraries
Link: http://www.white-hat-web-design.co.uk/articles/php-captcha.php

This program is free software; you can redistribute it and/or 
modify it under the terms of the GNU General Public License 
as published by the Free Software Foundation; either version 2 
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, 
but WITHOUT ANY WARRANTY; without even the implied warranty of 
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
GNU General Public License for more details: 
http://www.gnu.org/licenses/gpl.html