function createRequestObject()
{	
	xhr=null;//firefox
	if (window.XMLHttpRequest) {
	xhr = new XMLHttpRequest();

	// Handling Safari/firefox bug :
	if (xhr.overrideMimeType) {
	xhr.overrideMimeType("text/html");
	//xhr.overrideMimeType("text/xml");
	}

	} else {

	if (window.ActiveXObject) {

	try { // IE IE
	xhr = new ActiveXObject("Msxml2.XMLHTTP");
	} catch (e) {
	try { // Others IE
	xhr = new ActiveXObject("Microsoft.XMLHTTP");
	} catch (e) {
	window.alert("Your navigator doesn't handle AJAX, please use Internet explorer, Safari or firefox");
	} // try-catch
	} // try-catch

	}

	} // if-else

	return xhr;

}

var is_ie;
if (navigator.appName=='Microsoft Internet Explorer')
{
	is_ie=true;
}
else
{
	is_ie=false;
}