var calendar1, calendar2; /*must be declared in global scope*/
/*put the calendar initializations in the window's onload() method*/
window.onload = getCalendar() {
	dateChooser = new Epoch('cal1','popup',document.getElementById('calendar1_container'),false);
	calendar2 = new Epoch('cal2','popup',document.getElementById('calendar2_container'),false);
	...
};