HTTP-GET Request cross-domain - Security issue

Hej!

Jeg skal sende en get forespørgsel til et andet domæne end, der hvor min løsning ligger.

Jeg har følgende kode:
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Xml.Linq;
using System.Net;
using System.IO;
using System.Security.Permissions;

namespace SMS_gateway
{
   
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.High)]
    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            try
            {
                WebRequest req = WebRequest.Create("http://int.etdomae.ne/somewhere/?msg=Test&rec=xxxxxxxxxx&sapid=xxxx&password=xxxxxxxx");
                req.Credentials = CredentialCache.DefaultNetworkCredentials;
                HttpWebResponse response = (HttpWebResponse)req.GetResponse();
                Stream dataStream = response.GetResponseStream();
                StreamReader reader = new StreamReader(dataStream);
                string responseFromServer = reader.ReadToEnd();
                reader.Close();
                dataStream.Close();
                response.Close();
                resulttxt.Text = responseFromServer;
            }catch(Exception ex){
                resulttxt.Text = ex.StackTrace;
            }
        }
    }
}

Hvordan knækker jeg lige den?