We have gotten recaptcha working on 1.5 and setup so you can too. Its a core hack, and we took the privs for providing a backup file as well so you dont have to.

We made is so all people registering for your site and using normal registration methods have to now type in the recaptcha and all people using the normal contacts component have to use the recaptcha and all admins... Wait why admins... Well most people do not change the Super Admins username from admin... so all a bot has to do is use your admin username and brute force the password... Now they cant.

To see this work view;

http://www.object6.com/administrator
http://www.joomlamafia.com/component/user/?task=register
http://www.joomlamafia.com/contact-us.html

for more information http://recaptcha.net/learnmore.html

We change 6 files and add 3 lines to 1 login.css thats for the admin template.

Get your copy here