Facebook - hide content on website till "Like" button clicked...

Question

I'm using the wordpress plugin from http://www.sociable.es/facebook-wordpress-plugin-3-0/ on my blog, and I try to figure out, how they hide their download till I click the "Like" button on the post.

I tried:

<fb:fbml version="1.1">
<fb:visible-to-connection>HIDDEN CONTENT</fb:visible-to-connection>
</fb:fbml>

But it didn't work.

Is there a way with the Javascript SDK or any other solution?

Thanks a lot!