ACS Friends search runs only for admin user ?

Hi, I have an issue on ACS Friends search.

My app lists/totalize all followers for some users end It was OK .

But from yesterday it stops working well; it lists only friends for admin/login user. If I try to search using an user_id that is not an app admin,(I am logged as normal user) I obtain a 403 error about permissions .

I am testing on ios 7 ,Android 4.2 devices and simulators.

Titanium SDK 3.3

this is my sample code :

    var tot_follower = 0;
    Cloud.Friends.search({
        user_id:  'some_user_id', 
        followers : 'true',
        response_json_depth : 1 
    }, function (eFr2) {
            if (eFr2.success) {
                if (eFr2.users.length == 0) {
                    // no friends   
                } else {
                    tot_follower = eFr2.users.length;
                }
            }       
    });

Can someone help me ? thanks

Alberto Pace