function updateClock()
{
  var ct = new Date();

  var ch = ct.getHours();
  var cm = ct.getMinutes();
  ch = ( ch < 10 ? "0" : "" ) + ch;
  cm = ( cm < 10 ? "0" : "" ) + cm;

  var cts = ch + ":" + cm;

  document.getElementById("clock").firstChild.nodeValue = cts;
}