function createRequestObject() {
	if (window.XMLHttpRequest) {
		try {
			return new XMLHttpRequest();
		} catch (e) { alert(e); }
	} else if (window.ActiveXObject) {
		try {
			return new ActiveXObject('Msxml2.XMLHTTP');
		} catch (e) { alert(e); }
		try {
			return new ActiveXObject('Microsoft.XMLHTTP');
		} catch (e) { alert(e); }
	}
	return null;
}