I’ve updated my Comment License plugin to make it look nicer in WordPress 2.5.
This plugin shows a license with terms of your choosing in your comments form. You can edit the terms of your license in the options page. You can see it in use on my site wherever there are comment forms.
The download and more information are available on my WordPress Plugins page.
If you have any trouble with this, please open a thread in the WP Support Forums and send me the link.