var request = null;

try {
	request = new XMLHttpRequest();
} catch (trymicrosoft) {
	try {
		request = new ActiveXObject("Msxm12.XMLHTTP");
	} catch (othermicrosoft) {
		try {
			request = new ActiveXObject("Microsoft.XMLHTTP");
		} catch (failed) {
			request = null;
		}
	}
}
if (request == null)
	alert("Error creating request object!");