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; } }
if (roll == 'true') {
    menu_home       = new Image; menu_home.src       = "images/home2.gif";
    menu_sitemap       = new Image; menu_sitemap.src       = "images/sitemap2.gif";
    menu_partners       = new Image; menu_partners.src       = "images/partners2.gif";
    menu_contact_us       = new Image; menu_contact_us.src       = "images/contact_us2.gif";
}