var http_request = false;

function makeRequest(url, response) {
  http_request = false;
   
  if (window.XMLHttpRequest) { // Mozilla, Safari,...
    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('Giving up :( Cannot create an XMLHTTP instance');
    return false;
  }

  // Add in remote calls here
  if( response == "update_cart") {
    http_request.onreadystatechange = function() { alertContents_update_cart(); };
    response_type = true;
  } 

  if( response == "get_cart") {
    http_request.onreadystatechange = function() { alertContents_get_cart(); };
    response_type = true;
  }

  if( response == "learn_more") {
    new Effect.ScrollTo('learn_more', {offset: -15});
    http_request.onreadystatechange = function() { alertContents_learn_more(); };
    response_type = true;
  }

  http_request.open('POST', url, response_type);
  http_request.send(null);
}