Trigger a function when Like Button on top of a page clicked

I'm writing FBML code for my tab on my fan page and I want the visitors see only an image on开发者_开发问答 that Welcome Tab since they click "Like" button on top of the page, just next to page name. When users like my page, then I'll show a content in that tab.

I'm trying to do something like this: http://www.facebook.com/901Tequila?v=ap … 4904458780

I just don't know how I know my like button is pressed. Obviously, I cannot use: "FB.Event.subscribe('edge.create',..." in FBML and I don't know if there is FBJS equivalent of this function.

If there is a way to do this, I'm willing to hear. Thanx