if (document.getElementById('dt_secs')!=null) {
  var laikas = new Date();
  var ch = laikas.getHours();
  var ghe = document.getElementById('GMTH');
  if (ghe!=null) { var gh = ghe.value; } else { var gh = 0; }
  var gme = document.getElementById('gmtdiff');
  if (gme!=null) { gme.value = ch - gh; }
  var t=setTimeout('laikas=naujinkLaika()',1000);
}