function validateStartTime(source, args)
{				
	var tzdd = document.getElementById("tzMain_ddlTimeZone");
	if (tzdd == null) return; 
	
	var timeZone = tzdd.value.toString();
				
	var dteLocal = new Date();
	var dteSummer = new Date("7/1/00");
	var dteWinter = new Date("1/1/00");
	var currentOS;
	var winterOS;
	var summerOS;
	var tzOS;
			
	localOS = dteLocal.getTimezoneOffset() / 60;
	winterOS = dteWinter.getTimezoneOffset() / 60;
	summerOS = dteSummer.getTimezoneOffset() / 60;
	//alert('localOS: ' + localOS);
	//alert('winterOS: ' + winterOS);
	//alert('summerOS: ' + summerOS);

	if (localOS == winterOS)
	{
		switch (timeZone)
		{
			case "0" :
				tzOS = 0;
				break;
			case "1" :
				tzOS = -10;
				break;
			case "2" :
				tzOS = -9;
				break;
			case "3" :
				tzOS = -8;
				break;
			case "4" :
				tzOS = -7;
				break;
			case "5" :
				tzOS = -7;
				break;
			case "6" :
				tzOS = -6;
				break;
			case "7" :
				tzOS = -6;
				break;
			case "8" :
				tzOS = -5;
				break;
			case "10" :
				tzOS = -4;
				break;
		}
	}
	else
	{
		switch (timeZone)
		{
			case "0" :
				tzOS = 0;
				break;
			case "1" :
				tzOS = -10;
				break;
			case "2" :
				tzOS = -8;
				break;
			case "3" :
				tzOS = -7;
				break;
			case "4" :
				tzOS = -7;
				break;
			case "5" :
				tzOS = -6;
				break;
			case "6" :
				tzOS = -5;
				break;
			case "7" :
				tzOS = -6;
				break;
			case "8" :
				tzOS = -4;
				break;
			case "10" :
				tzOS = -3;
				break;	
		}
	}
				
	var calDate = document.getElementById("calEvent");					
	var start = new Date(calDate.value);	
	var startDT = new Date(start.toDateString() + ' ' + args.Value);
	
	var adjStartDT = new Date(Date.UTC(startDT.getFullYear(), startDT.getMonth(), startDT.getDate(), startDT.getHours() - tzOS, startDT.getMinutes() ));
	//alert('adjStartDT: ' + adjStartDT);
	
	var utc = new Date();
	//alert ('utc: ' + utc.toUTCString());
	
	var timeDiff = adjStartDT.getTime() - utc.getTime();				
	//alert('adjStart-time: ' + adjStartDT.getTime() + 'utc-time:' + utc.getTime() + '; diff: ' + timeDiff.toString() );
																						
	if (timeDiff < 0)
		args.IsValid = false;
}