var popupCalendar;

// Date selected.
function selected(cal, date) {
	cal.sel.value = date;
	if (cal.dateClicked) {
		cal.callCloseHandler();
    }
}

// Close popup.
function closeHandler(cal) {
	cal.hide();
	popupCalendar = null;
}

function showCalendar(id, buttonID, format) {
	var el = document.getElementById(id);
	if (popupCalendar != null) {
		popupCalendar.hide();
	} else {
		var cal = new Calendar(0, null, selected, closeHandler);
		cal.weekNumbers = false;
		cal.showsOtherMonths = true;
		popupCalendar = cal;
		cal.setRange(1900, 2070);
		cal.create();
	}
	
	popupCalendar.setDateFormat(format);
	popupCalendar.parseDate(el.value);
	popupCalendar.sel = el;

	popupCalendar.showAtElement(document.getElementById(buttonID), "Br");
	return false;
}