function initRollOvers() {
	$$(".pics img").each(function(elt) {
		if(!elt.src.include("-over")) {
			Event.observe(elt, "mouseover", onMouseOver);
			Event.observe(elt, "mouseout", onMouseOut);
		}
	});
} // initRollOvers

function onMouseOver(evt) {
	var elt = Event.element(evt);
	var attr = $(elt).readAttribute("src");
	var pos = attr.lastIndexOf(".");
	elt.writeAttribute("src", attr.slice(0, pos).concat("-over", attr.slice(pos)));
} // onMouseOver

function onMouseOut(evt) {
	var elt = Event.element(evt);
	elt.writeAttribute("src", $(elt).readAttribute("src").gsub("-over", ""));
} // onMouseOut

Event.observe(window, "load", initRollOvers);