browser_name = navigator.appName; 
browser_version = parseFloat(navigator.appVersion); 
if (browser_name == "Netscape" && browser_version >= 3.0) { roll = 'true'; } 
else if (browser_name == "Microsoft Internet Explorer" && browser_version >= 3.0) { roll = 'true'; } 
else { roll = 'false'; } 
function show(where){ 
if (roll == 'true'){ 
stored=where; 
storedLocation=document.images[where].src; 
document.images[where].src="/i/m1.gif";} 
} 
function hide(){ 
if (roll == 'true') document.images[stored].src=storedLocation;}