// JavaScript Document
var ajax=false;

function iniciaAjax(){
   try {
         ajax = new ActiveXObject("Msxml2.XMLHTTP");
   } catch (e) {
         try {
                ajax = new ActiveXObject("Microsoft.XMLHTTP");
         } catch (E) {
               try{
                   ajax = new XMLHttpRequest();
               } catch(E2){
                    ajax = false;
               }
         }
    }
   if (!ajax && typeof XMLHttpRequest!='undefined') {
        ajax = new XMLHttpRequest();
   }
}