I'm using PHP and Zend to pull in my videos from YouTube. I'm authenticated with AuthSub and can post comments successfully.

I now wish to click on 'like' or 'dislike'.
The PHP API guide only has the old star rating detailed:
<http://code.google.com/apis/youtube/2.0/developers_guide_php.html#Adding_a_Rating>

But how can I do the same thing for the new rating system?