// currently only checks to see whether the browser is Macish
// go to http://www.webreference.com/ for more tests
    var appVer = navigator.appVersion.toLowerCase();
    var is_minor = parseFloat(appVer);
    var is_major = parseInt(is_minor);
    var agt=navigator.userAgent.toLowerCase();
    var is_gecko = ((navigator.product)&&(navigator.product.toLowerCase()=="gecko"))?true:false;
    var is_moz   = ((agt.indexOf('mozilla/5')!=-1) && (agt.indexOf('spoofer')==-1) &&
                    (agt.indexOf('compatible')==-1) && (agt.indexOf('opera')==-1)  &&
                    (agt.indexOf('webtv')==-1) && (agt.indexOf('hotjava')==-1)     &&
                    (is_gecko) && 
                    ((navigator.vendor=="")||(navigator.vendor=="Mozilla")));
    var is_nav  = ((agt.indexOf('mozilla')!=-1) && (agt.indexOf('spoofer')==-1)
                    && (agt.indexOf('compatible') == -1) && (agt.indexOf('opera')==-1)
                    && (agt.indexOf('webtv')==-1) && (agt.indexOf('hotjava')==-1)
                    && (!(is_moz)));
    var is_nav4 = (is_nav && (is_major == 4));
    var is_mac    = (navigator.userAgent.toLowerCase().indexOf("mac")!=-1);