var xmlHttp
var xmlHttp2

function mostrarContenido(str1,str2) {
xmlHttp=GetXmlHttpObject();
xmlHttp2=GetXmlHttpObject();
if (xmlHttp==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  } 

if (xmlHttp2==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  } 


xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET",str1,true);
xmlHttp.send(null);

xmlHttp2.onreadystatechange=stateChanged;
xmlHttp2.open("GET",str2,true);
xmlHttp2.send(null);

}

function stateChanged() 
{ 
if (xmlHttp.readyState==4)
{ 
document.getElementById("dir").innerHTML=xmlHttp.responseText;
}

if (xmlHttp2.readyState==4)
{ 
document.getElementById("menu").innerHTML=xmlHttp2.responseText;
}
}

function GetXmlHttpObject()
{
var xmlHttp=null;

try
  {
  // Firefox, Opera 8.0+, Safari
  xmlHttp=new XMLHttpRequest();
  }
catch (e)
  {
  // Internet Explorer
  try
    {
    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
    }
  catch (e)
    {
    xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
  }
return xmlHttp;
}