JSONP 401未经授权的错误

I'm trying to implement a jsonp function but I'm getting a 401 response,

code on website1:

   goaap: function () {
        $.ajax({
            Authorization: '',
            type: 'GET',
            url: 'http://www.wedsite2.com/global/js/live.js?callback=goaa',
            async: false,
            contentType: "application/json; charset=utf-8",
            dataType: 'jsonp',
            success: function (msg) {
                    //do something
              }
        });
    },

code on website2:

goaa: function () {
        var request = null;
        while (request === null) {
            request = $.ajax({
                url: "default.aspx/goaa",
                data: '{AID: "' + $('#details').data('aid') + '"}',
                dataType: 'json',
                type: "POST",
                contentType: "application/json; charset=utf-8"
            });
        }
        return request;
    },

I have looked at a number of examples and they suggest the jsonp implementation is straight forward, have I missed something in my implementation which is causing the 401 response?

Extra information from firebug:

Response:

{"Message":"There was an error processing the request.","StackTrace":"","ExceptionType":""}

JSON:

Message "There was an error processing the request." StackTrace "" ExceptionType ""

Post: JSON: AID "-1" Source: {AID: "-1"}