var last_id = 0;

function getAjaxData(arch,interval) {
        $.ajax({
          url: 'ajaxgielda.php',
          data: 'data='+arch,
          dataType: 'html',
          type: 'post',
          success: function (j) {
              $('#gieldowyExpress').html(j); 
              var curent_id = $('#gieldowyExpress .lastinsert').get(0).id;
            
              if(curent_id != last_id){
                  $('#gieldowyExpress .gieldaonline ').fadeOut("slow").fadeIn("slow");
                  last_id = $('#gieldowyExpress .lastinsert').get(0).id;
              }
          }
        });
    timer = setTimeout('getAjaxData('+arch+','+interval+')',interval)
}