FaceBook Connect: Error logging in?

Question

when i click the login button, i get the following javascript error:

FB.getLoginStatus is not a function
[Break on this error] FB.getLoginStatus(function(response) { 

here's my code:

<script type="text/javascript">
<!--
    $(document).load(function() {

    });

    FB.init("56800990388df98bfe358812eb6caf3d", "xd_receiver.htm");
    FB.Event.subscribe('auth.login', function(response) {
        window.location.reload();
    });

    FB.getLoginStatus(function(response) {
        if (response.session) {
            // logged in and connected user, someone you know
            fb_login.hide();
        } else {
            // no user session available, someone you dont know

        }
    });

// -->
</script>

and the login button:

<fb:login-button v="2">Log In with Facebook</fb:login-button>