function NestedAjaxCalls() {
          var ajax_connection = createRequest();
          ajax_connection.open('get', 'request1.php');
          ajax_connection.onreadystatechange = function() {
            ResponseHandler1(ajax_connection);
          }
          ajax_connection.send(null);
      }

      function ResponseHandler1(ajax_connection) {
        var ajax_connection2 = createRequest();
        ajax_connection2.open('get', 'request2.php');
        ajax_connection2.onreadystatechange = function() {
          ResponseHandler2(ajax_connection);
        }
      }

      function ResponseHandler2(ajax_connection) {
        // Does not get called
        echo('Success! Nested AJAX call was made successfully.');
      }

      // create an AJAX Request
      function createRequest() {
        var ajaxRequest;

        try
        {
          ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
        }
          catch (e1)
          {
            try
            {
              ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
            }
              catch (e2)
              {
                ajaxRequest = new XMLHttpRequest();
              }
          }

        return ajaxRequest;
      }

Is it something simple I'm doing wrong like the scope of my connection
variables or is this a limitation with AJAX - if so could anyone
suggest an alternative method of doing the same thing? Any replies
gratefully received...