function Browser() 
   {  var ua, s, i;
      this.isIE    = false;
      this.isNS    = false;
      this.version = null;

      ua = navigator.userAgent;
      s = "MSIE";  if ((i = ua.indexOf(s)) >= 0){ this.isIE = true;this.version = parseFloat(ua.substr(i + s.length));return;}
      s = "Netscape6/";   if ((i = ua.indexOf(s)) >= 0) {  this.isNS = true; this.version = parseFloat(ua.substr(i + s.length)); return;}
      s = "Gecko"; if ((i = ua.indexOf(s)) >= 0) { this.isNS = true; this.version = 6.1; return;}
   }
   var browser = new Browser();