prettyPhoto video in lightbox doesn’t work

I have read the documenation on the prettyPhoto site and I don’t get it to work.

I can see that the theme has support for it, since it uses it on several places, but that is for images.

this is the code I use, but it doesn’t work, it just goes to the youtube video on youtube.com

Click to open video in lightbox

Please advise.

Regards,
Dan