CB Captcha 2.4 (on J1.5.26): GD + Freetype Not Installed - what is fix?

Hi. My other two Joomla! 1.5.26 sites have CB-quickstart-pro_1.4.zip installed ok, group jive (261) got installed ok, etc. mod_cblogin is enabled and appears aok on the frontend. CB Captcha works fine on these two sites. CBLogin works fine as well. A working cblogin 'panel' with-captcha is an important asset for all 3 sites.

However, my 3rd site should have the same extensions and cb plugins installed c/o CB-quickstart-pro_1.4.zip, and it appears it does. All are running on the same web host w/ the same PHP and php.ini file. But on the 3rd site, CB Captcha 2.4 plugin backend UI says (in RED) "GD and Freetype" are not installed! Somehow those two "bits" are installed ok on the first two sites (i.e. those two "bits" are displayed in green).

I have NO IDEA how to install these "bits" (GD+Freetype) or what downloads to look for on joomlapolis.com, nor do I know if they are Joomla or CB modules or plugins or if they are PHP "code pieces", which as I said above they should not be. I have no idea how to UNINSTALL all the bits that CB-quickstart-pro_1.4 installed, nor which could be missing, unless I have to use a checklist of the 'components' in quickstart from joomlapolis and delete each one to become able to "start over." Some CB fields and tabs and several lists from CB 1.8 were pre-existing. I don't want to loose them.

However having cited all those conditions, getting CB Captcha 2.4 to work and having cblogin work on most of the 3rd site's web pages, is FIRST PRIORITY.

HELP PLEASE!

Details of CB Captcha plugin UI's right hand side errors are as follows:

Version: Version 2.4 (compatible with CB facebook/twitter connect plugins)
Release Date: 07 Apr 2010
Credits: This plugin was created by Nant and Beat. Captcha image code is based on script www.white-hat-web-design.co.uk/articles/php-captcha.php - audio sounds taken from www.chimeric.de/projects/npa project.
License: This plugin is distributed under a limited GNU/GPL v2 license

Plugin Prerequisites
Captcha Requirements: GD: GD NOT INSTALLED!!!
Freetype: FREETYPE NOT INSTALLED!!!

Following a tip in an older Captcha problem thread, I checked the "PHP Info" c/o Help->System Info->PHP Info tab. Turns out that the 3rd site with "no GD, no Freetype" is running PHP 5.3.6. The other two sites that run aok, have GD & Freetype installed ok, are running on PHP 5.2.17. I'm not yet sure how my public web host sys-admin makes that work for all my sites. But just perhaps that is where the problem lies. Thanks to any who were thinking about thinking about this problem on my behalf.

Please open ticket with you host helpdesk and ask them to enable these for you.