var request = null;
function createRequest() {
	try {
	  request = new XMLHttpRequest();
	} catch (trymicrosoft) {
	  try {
	    request = new ActiveXObject("Msxml2.XMLHTTP");
	  } catch (othermicrosoft) {
	    try {
	      request = new ActiveXObject("Microsoft.XMLHTTP");
	    } catch (failed) {
	      request = null;
	    }
	  }
	}
	
	if (request == null)
	  alert("Error creating request object!");
}