function rollover(id, base, index) {
	var el_id = id;
	if (index) {
		el_id = el_id + "_" + index;
	}
	var el = document.getElementById(el_id);
	if (el) {
		el.src = base + id + "_f2.gif";
	}
}

function rollout(id, base, index) {
	var el_id = id;
	if (index) {
		el_id = el_id + "_" + index;
	}
	var el = document.getElementById(el_id);
	if (el) {
		el.src = base + id + "_f1.gif";
	}
}