if (document.images) {
	home_on = new Image(); home_on.src="images/home_on.gif";
	home_off = new Image(); home_off.src="images/home_off.gif";
	events_on = new Image(); events_on.src="images/events_on.gif";
	events_off = new Image(); events_off.src="images/events_off.gif";
	contacts_on = new Image(); contacts_on.src="images/contacts_on.gif";
	contacts_off = new Image(); contacts_off.src="images/contacts_off.gif";
	links_on = new Image(); links_on.src="images/links_on.gif";
	links_off = new Image(); links_off.src="images/links_off.gif";
	}  
       
function roll_over(imgName) {
            if (document.images) {
            imgOn = eval(imgName + "_on.src");
            document [imgName].src = imgOn;
            }
    }

function roll_out(imgName) {
            if (document.images) {
            imgOff = eval(imgName + "_off.src");
            document [imgName].src = imgOff;
            }
    }