function initProductDetailsFields() {
	if($("serial1")) {
		Event.observe("serial1","keyup", checkKeycode );
		Event.observe("serial1","keyup",function() { charCount('serial1',3) });
		Event.observe("serial2","keyup", checkKeycode );
		Event.observe("serial2","keyup",function() { charCount('serial2',2) });
		Event.observe("day","keyup", checkKeycode );
		Event.observe("day","keyup",function() { charCount('day',2) });
		Event.observe("month","keyup", checkKeycode );
		Event.observe("month","keyup",function() { charCount('month',2) });
	}
}
var keycode;
function checkKeycode(e) {
	if (window.event) keycode = window.event.keyCode;
	else if (e) keycode = e.which;
}
function charCount(eid,len,e) {
	if(keycode!=9 && keycode!=16) {
		if($F(eid).length==len) {
			switch(eid) {
			case "serial1" :
				$("serial2").focus(); break;
			case "serial2" :
				if($("serial3")) $("serial3").focus(); break;
			case "day" :
				$("month").focus(); break;
			case "month" :
				$("year").focus(); break;
			}
		}
	}
	keycode = 0;
}

Event.observe(window,"load", function() { initProductDetailsFields() })