Which is the PHP api to know if user facebook is an app fan or not -before the app authentication-?

Question

I know there is this api to detect if an user is fan or not of an application

$facebook->api("me/likes/PAGE_ID");

but this function works only after you are authenticated.

I would like to know how could I get this information only when I reach my homepage applicatipn with me logged on facebook but not yet authenticated on the application. is it possible?

thanks in advance