Author: David Nishimoto
<script language=javascript>
	var timerID = 0;
	var tStart  = null;
		
	function UpdateTimer(iMilliseconds) {
	   if(timerID) {
	      clearTimeout(timerID);
	      clockID  = 0;
            }

	   if(!tStart)
	      tStart   = new Date();
	      var   tDate = new Date();
	      var   tDiff = tDate.getTime() - tStart.getTime();
	      tDate.setTime(tDiff);

	      alert('Insert your Code here');	
		
	      timerID  = setTimeout("UpdateTimer("+iMilliseconds+")",iMilliseconds); 
	}

	function SetTimer(iMilliseconds) {
	   tStart   = new Date();
	   timerID  = setTimeout("UpdateTimer("+iMilliseconds+")", iMilliseconds);
	}
	SetTimer(3000);
</script>