function get_xmlhttp()
{
  var xmlhttp;
  
  /*@cc_on
  @if (@_jscript_version >= 5)
    try {
      xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
      try {
        xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
      } catch (E) {
        xmlhttp = false;
      }
    }
  @else
  xmlhttp = false;
  @end @*/
  
  if (!xmlhttp && typeof XMLHttpRequest != 'undefined') {
    try {
      xmlhttp = new XMLHttpRequest();
    } catch (e) {
      xmlhttp = false;
    }
  }
  return xmlhttp;
}

function makePostRequest(url, parameters, retFunction)
{
	http_request = get_xmlhttp();
	
	if (!http_request)
	{
		alert('Cannot create XMLHTTP instance');
		return false;
	}
	
	http_request.onreadystatechange = eval(retFunction);
	http_request.open('POST', url, true);
	http_request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
	http_request.send(parameters);
	previous_request = false;
}

function makeRequest(url, parameters, retFunction)
{
	http_request = get_xmlhttp();
	
	if (!http_request)
	{
		alert('Cannot create XMLHTTP instance');
		return false;
	}
	
	http_request.onreadystatechange = eval(retFunction);
	http_request.open('GET', url + '?' + parameters, true);
	http_request.send(null);
	previous_request = false;
}