//op ΰΎΤθΑ
function ChangeEndDay(obj){

		var day=document.getElementById(obj+"_day");
		var month=document.getElementById(obj+"_month").value;
		var year=document.getElementById(obj+"_year").value;
		var test=day.selectedIndex;
		var endDay=findNumDay(month,year);
		var selDay=day.value;
		if(parseInt(selDay) > parseInt(endDay)){
			selDay=endDay;
		}

		if(day.options[0].value==0){// have select
			isselect=1;
		}

		day.innerHTML="";
		if(navigator.appName != "Netscape"){//Check Browser ΆΝ§ FireFox
			if(isselect==1){
				var oOption = document.createElement("OPTION");
				oOption.value="0";
				oOption.text="-ΗΡΉ·Υθ-";
				day.add(oOption);
			}
			for(var i=1;i<=endDay;i++){
				var oOption = document.createElement("OPTION");
				oOption.value=i;
				oOption.text=i;
				day.add(oOption);
			}
			day.value=selDay;
		}else{// IE
			if(isselect==1){
				var oOption = document.createElement("OPTION");
				oOption.value="0";
				oOption.text="-ΗΡΉ·Υθ-";
				day.appendChild(oOption);
			}
			for(var i=1;i<=endDay;i++){
				var oOption = document.createElement("OPTION");
				oOption.value=i;
				oOption.text=i;
				day.appendChild(oOption);
			}
			day.value=selDay;
		}
}

function findNumDay(month,year){
	if(year%4==0){
		var myArray = ["31", "31", "29", "31", "30", "31", "30", "31", "31", "30", "31", "30", "31"];
	}else{
		var myArray = ["31", "31", "28", "31", "30", "31", "30", "31", "31", "30", "31", "30", "31"];	
	}
	return myArray[month];
}