// adds rollover effects to anything that has class='roll'
jQuery(document).ready(function() {
    $(".roll").hover(
    function() {
	var iconName = $(this).attr("src");
	var original = iconName.split(".png")[0];
	var imageName = original + "-hover.png";
	$(this).attr({ src: "" + imageName });
    },
    function() {
	var iconName = $(this).attr("src");
	var original = iconName.split("-hover.")[0];
	var imageName = original + ".png";
	$(this).attr({ src: "" + imageName });
    });
});