Using current_user(obj) externally in 3.1

This used to work in previous versions:
include_once ‘../../../wp-config.php’;
include_once ‘../../../wp-load.php’;
include_once ‘../../../wp-includes/wp-db.php’;
include_once ‘functions.php’;

return $current_user->ID;

But now, it’s returning 0.

I have an upload.php file that one of my jquery upload scripts is using, and I’d like to use $wpdb, and $current_user objects, but it’s not working.

Any ideas?