AJAX with Remote WCF Services

Hi, i not sure this is the right place to post or not
but i got problem regarding invoke the wcf from ajax.
 
currently i make a WCF services and host at my localhost, http://localhost/MyService
and i make a default page, http://localhost/MyService/default.aspx to test and it run witout problem.
(Code From Sample tutorial  http://dotnetslackers.com/articles/ajax/JSON-EnabledWCFServicesInASPNET35.aspx)
Code Below:
WCF:
[ServiceContract(Namespace = "test")]
    [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
    public class TimeService
    {
        // Add [WebGet] attribute to use HTTP GET
        [OperationContract]
        public DateTime GetTime() 
  &nb ...