function sendNewsletter(src) {
  http_request = false;
  if (window.XMLHttpRequest) {http_request = new XMLHttpRequest();
    if (http_request.overrideMimeType) {http_request.overrideMimeType('text/xml');}
  }
  else if (window.ActiveXObject) { // IE
    try {http_request = new ActiveXObject("Msxml2.XMLHTTP");} catch (e) {
      try {http_request = new ActiveXObject("Microsoft.XMLHTTP");} catch (e) {}
    }
  }
  if (!http_request) {alert('The Request Object could not be created! Please check your JAVA settings!');
  return false;
  }
   
  var postData = "subscriber_name="+encodeURIComponent(document.getElementById('subscriber_name').value)+"&subscriber_email="+document.getElementById('subscriber_email').value+"&referal_code=nlsu2012";
  http_request.onreadystatechange = feedback_subscription;
  http_request.open('POST', src, true);
  http_request.setRequestHeader("Content-Type","application/x-www-form-urlencoded;");
  http_request.send(postData);
}

function feedback_subscription() {
  if (http_request.readyState < 4) {
    document.getElementById("newsletter_signup").innerHTML = 'Please wait...';
  }
  if (http_request.readyState == 4) {
    document.getElementById("newsletter_signup").innerHTML = http_request.responseText;
  }
}