function objetoAjax(){
 var xmlhttp=false;
  try{
   xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
  }catch(e){
   try {
    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
   }catch(E){
    xmlhttp = false;
   }
  }
  if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
   xmlhttp = new XMLHttpRequest();
  }
  return xmlhttp;
}


function tab1(){
     divContenido = document.getElementById('tabs');	 
     ajax=objetoAjax();
     ajax.open("GET", "2010/web2010_js/bus_prod.php");
	 divContenido.innerHTML= '<center><img src="2010/web2010_js/loading_bar.gif"></center>'; 	 
     ajax.onreadystatechange=function() {
      if (ajax.readyState==4) {
           divContenido.innerHTML = ajax.responseText;
      }
 }
 ajax.send(null)
}

function tab2(){
     divContenido = document.getElementById('tabs');	 
     ajax=objetoAjax();
     ajax.open("GET", "2010/web2010_js/bus_cert.php");
	 divContenido.innerHTML= '<center><img src="2010/web2010_js/loading_bar.gif"></center>'; 	 
     ajax.onreadystatechange=function() {
      if (ajax.readyState==4) {
           divContenido.innerHTML = ajax.responseText;
      }
 }
 ajax.send(null)
}