function hotelreservierung_validate() {
	var emptyfields = 0;
	var mandatoryfields = 0;
	var inputfields = document.hotelreservierung.getElementsByTagName('input');
	for (var i = 0; i < inputfields.length; i++) {
		if (inputfields[i].className == 'mandatory' || inputfields[i].className == 'jscalendar mandatory') {
			if (inputfields[i].value == '') { emptyfields += 1; }
		}
	}
	if (emptyfields == 0) { return true; } else { alert('Bitte füllen Sie alle Pflichtfelder aus\n\nPlease fill in all mandatory fields.'); return false; }
}