function Ajax_start() {
	try {
        // create ActiveXObject
        objAjax = new ActiveXObject('Msxml2.XMLHTTP');
    } catch(e) {
        try {
            objAjax = new ActiveXObject('Microsoft.XMLHTTP');
        } catch (E) {
            objAjax = false;
        }
    }    
    if (!objAjax && typeof XMLHttpRequest != 'undefined') {
        objAjax = new XMLHttpRequest();
    }
}