function logout(url) {
    if (FBU_id > 0) {
        //logout of fb before redirect to logout page.
        //FB.ensureInit(function() { FB.Connect.logoutAndRedirect(BDP.go('logout', null, true)); });
        FB.ensureInit(function() {
            //FB.Connect.Logout().waitUntilReady(function( status ) {BDP.go('logout');}); });//BDP.go('logout')); });
            FB.Connect.logout(function() { location.href=url });
        });
    } else {
        location.href=url;
    }
}