function registerImage(imgName) {
	eval(imgName + "_on = new Image()");
	eval(imgName + "_on.src = \"/img/" + imgName + "_on.gif\"");
	eval(imgName + "_off = new Image()");
	eval(imgName + "_off.src = \"/img/" + imgName + "_off.gif\"");
}

function on(imgID) {
	img = document.getElementById(imgID);
	img.src = eval(imgID + "_on.src");
}

function off(imgID) {
	img = document.getElementById(imgID);
	img.src = eval(imgID + "_off.src");
}

//register rollovers
registerImage("moto");