browser_name = navigator.appName;
browser_version = parseFloat(navigator.appVersion);

if (browser_name == "Netscape" && browser_version < 2.0)
        {allow = 'false';}
else if (browser_name == "Netscape" && browser_version == 2.0)
        {allow = 'false';}
else if (browser_name == "Netscape" && browser_version >= 3.0)
        {allow = 'true';}
else if (browser_name == "Microsoft Internet Explorer" && browser_version <= 2.0)
        {allow = 'false';}
else if (browser_name == "Microsoft Internet Explorer" && browser_version >= 2.0)
        {allow = 'true';}
else
        {allow = 'false';}

if (allow == 'true')
        {
                var kn = new Image();
                        kn.src = "images/about_on.jpg";
                var kn6 = new Image();
                        kn6.src = "images/decol_on.jpg";
                var kn7 = new Image();
                        kn7.src = "images/posud_on.jpg";
                var kn8 = new Image();
                        kn8.src = "images/dekor_on.jpg";
       }

function rollOver( imgName ) {
    if ( eval("document." + imgName + ".src.search('_off') > 0 ")  ) {
        eval("document." + imgName + ".src = document." + imgName + ".src.replace('_off', '_on')");
    } else {
        eval("document." + imgName + ".src = document." + imgName + ".src.replace('_on', '_off')");
    }
}