no hace el POST y se pierden mis valores de variables

[annel_galvez]

// JavaScript Document
function XHConn()
{
var xmlhttp, bComplete = false;
try { xmlhttp = new ActiveXObject("Msxml2.XMLHTTP"); }
catch (e) { try { xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); }
catch (e) { try { xmlhttp = new XMLHttpRequest(); }
catch (e) { xmlhttp = false; }}}
if (!xmlhttp) return null;
this.connect = function(sURL, sMethod, sVars, fnDone)
{
if (!xmlhttp) return false;
bComplete = false;
sMethod = sMethod.toUpperCase();

try {
if (sMethod == "GET")
{
xmlhttp.open(sMethod, sURL+"?"+sVars, true);
sVars = "";
}
else
{
xmlhttp.open(sMethod, sURL, true);
xmlhttp.setRequestHeader("Method", "POST "+sURL+" HTTP/1.1");
xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
}
xmlhttp.onreadystatechange = function(){
if (xmlhttp.readyState == 4 && !bComplete)
{
bComplete=true;
fnDone(xmlhttp);
}};
xmlhttp.send(sVars);
}
catch(z) { return false; }
return true;
};
return this;
}