function updateday() {
	day = document.getElementById("hotelform").checkin_monthday.value;
	month = document.getElementById("hotelform").checkin_year_month.value.substr(5,2)-1;
	year = document.getElementById("hotelform").checkin_year_month.value.substr(0,4);
	arrcode= Date.parse(monthnames[month]+', '+day+' '+year);;

	dayobj = new Date();
	dayobj.setFullYear(year);
	dayobj.setMonth(month);
	dayobj.setDate(day);
	document.getElementById("hotelform").arrivalday.value = weekdays[dayobj.getDay()];

	day = document.getElementById("hotelform").checkout_monthday.value;
	month = document.getElementById("hotelform").checkout_year_month.value.substr(5,2)-1;
	year = document.getElementById("hotelform").checkout_year_month.value.substr(0,4);
	depcode= Date.parse(monthnames[month]+', '+day+' '+year);;

	depdayobj = new Date();
	depdayobj.setFullYear(year);
	depdayobj.setMonth(month);
	depdayobj.setDate(day);
	document.getElementById("hotelform").departureday.value = weekdays[depdayobj.getDay()];

	nights= Math.floor((depcode - arrcode) / (24*60*60*1000));
	if(nights>1)
		document.getElementById("hotelform").nights.value = nights + static_hotel_nights;
	else if(nights==1)
		document.getElementById("hotelform").nights.value = '1 ' + static_hotel_night;
	else 
		document.getElementById("hotelform").nights.value = 'Oops!';
	
}