function rolloverOn(name) {
	var imageSrc = eval('document.images["'+name+'"].src');
	var newImageSrc = imageSrc.replace("_off.","_on.");
	document.images[name].src = newImageSrc;
}

function rolloverOff(name) {
	var imageSrc = eval('document.images["'+name+'"].src');
	var newImageSrc = imageSrc.replace("_on.","_off.");
	document.images[name].src = newImageSrc;
}