function birth_submit(theForm){
	var w = 300;
	var h = 220;
	var new_window;

	var d = daymonth(theForm.month.options[theForm.month.selectedIndex].value);
	if(d < theForm.mday.value){
		alert("日が間違っています。"+ d + "日までです。");
		theForm.mday.focus();
		return(false);
	}

	new_window = window.open('','birth_open','scrollbars=0,toolbars=0,width=' + w + ',height=' + h);
	//new_window.moveTo(0,0);
	new_window.focus();
	return true;
}

/* 日付の範囲チェック */
function daymonth(month){	
	day = new Array(31,29,31,30,31,30,31,31,30,31,30,31);
	return day[month-1];
}