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 over(img,ref) { if (roll == 'true') {
document.images[img].src = ref; }  }
function out(img,ref) { if (roll == 'true') {
document.images[img].src = ref; } }