function markCalendarToday()
{
  var now = new Date();
  var dd  = now.getDate();
  var mm  = now.getMonth() +1;
  var yy  = now.getYear();
  dd = (dd < 10) ? "0" + dd : dd;
  mm = (mm < 10) ? "0" + mm : mm;
  if (yy < 999) yy += 1900;
  var id = "cal_" + yy + "-" + mm + "-" + dd;
  var elem = document.getElementById(id);
  if (elem)
  {
    elem.style.color = "#cc0000";
    elem.style.borderColor = "#cc0000";
  }
}