var Plattform = navigator.platform;
var welcherBrowser = navigator.appName;
var Ver = parseInt(navigator.appVersion);
var version = 0;
if (welcherBrowser == "Microsoft Internet Explorer" && Ver >= 3) version = "1"; 
if (welcherBrowser == "Netscape" && Ver >= 3) version = "1";
if (welcherBrowser == "Opera") version = "2";
if (welcherBrowser == "Netscape" && Ver >= 4) version = "3";
if (welcherBrowser == "Netscape" && Ver >= 5) version = "3"; 
if (welcherBrowser == "Microsoft Internet Explorer" && Ver >= 4) version = "4";
if ((Plattform == "MacPPC" || Plattform == "Mac68k") && welcherBrowser == "Microsoft Internet Explorer" && navigator.appVersion.substring(22,25) <= 4.5) version = "2";
if ((Plattform == "MacPPC" || Plattform == "Mac68k") && welcherBrowser == "Microsoft Internet Explorer" && navigator.appVersion.substring(22,25) >= 5.0) version = "5";
if (version == 0) version="4";