/********************* Standard Browsercheck *******************/

var old = parseInt(navigator.appVersion) < 4;
var userAgent = navigator.userAgent.toLowerCase();

var ns4Win = ((userAgent.indexOf("win") > -1) && (document.layers) && (userAgent.indexOf("netscape")));
var ns4Mac = ((userAgent.indexOf("mac") > -1) && (document.layers) && (userAgent.indexOf("netscape")));
var ns4Lin = ((userAgent.indexOf("linux") > -1) && (document.layers) && (userAgent.indexOf("netscape")));

var ieWin = ((userAgent.indexOf("win") > -1) && (document.all));
var ieMac = ((document.all) && (!ieWin) && (userAgent.indexOf("icab") < 0));
var opera = ((userAgent.indexOf("win") > -1) && (userAgent.indexOf("opera") > -1));
// fuer alle w3c compliant engines eg netscape mozilla gecko
var w3c = document.documentElement;

// differenzierung der 3 hauptbrowser
var isNav = ((ns4Win)||(ns4Mac)||(ns4Lin));
var isIE = ((ieWin)||(ieMac))&&(!opera);
var isW3C = ((w3c)&&(!isIE))||opera;