//gestione xmlHttp
var xmlHttp = CreaOggettoXmlHttp();

function CreaOggettoXmlHttp(){
	var xmlHttp;
	
	try{
		xmlHttp = new XMLHttpRequest();
	}
	catch(e){
		var XmlHttpVersions = new Array("MSXML2.XMLHTTP.6.0",
																		"MSXML2.XMLHTTP.5.0",
																		"MSXML2.XMLHTTP.4.0",
																		"MSXML2.XMLHTTP.3.0",
																		"MSXML2.XMLHTTP",
																		"Microsoft.XMLHTTP");
		for(var i=0; i<XmlHttpVersions.length && !xmlHttp; i++){
			try{
				xmlHttp = new ActiveXObject(XmlHttpVersions[i]);
			}
			catch(e){}
		}
	}
	
	if(!xmlHttp)
		alert("Errore nella creazione dell'oggetto");
	else
		return xmlHttp;
}