function openMonth(iyear,imonth) {
  var w2;
  var url;
  url = "http://www.ceder.net/tools/month_calendar.php4?Year=" + iyear + "&Month=" + imonth; 
  w2 = window.open(url,"monthwin","resizable,height=290,width=230,scrollbars=no");
  if (w2.window) {
    w2.window.focus();
  }
}