// Diverse Startwerte setzen
    // Browser-Variante abfragen
    var browser = new Object();
    var agent = navigator.userAgent.toLowerCase();
    browser.major = parseInt(navigator.appVersion);
    browser.minor = parseFloat(navigator.appVersion);
    browser.nav  = ( (agent.indexOf('mozilla') != -1 )
                  && (agent.indexOf('opera')== -1)
                  && (agent.indexOf('compatible') == -1) );
    browser.nav2 = (browser.nav && (browser.major >= 2));
    browser.nav3 = (browser.nav && (browser.major >= 3));
    browser.nav4 = (browser.nav && (browser.major >= 4));
    browser.ie   = (agent.indexOf("msie") != -1);
    browser.ie3  = (browser.ie && (browser.major == 2));
    browser.ie4  = (browser.ie && (browser.major >= 4));
    browser.ie5  = (browser.ie && (browser.major >= 5));
    browser.op   = (agent.indexOf("opera")!= -1);
    browser.unix = (agent.indexOf("x11")  != -1);
    browser.win  = (agent.indexOf("win")  != -1);
    browser.mac  = (agent.indexOf("mac")  != -1);
    n = 0;

    // Browser-Variante abfragen
    // Nur ab Netscape Version 3 und ab IE Version 4
    // und dazu kompatible (siehe oben) ausführen 
    if((browser.nav3) || (browser.ie4) )
    {
      imgOut  = new Array();
      imgOver = new Array();
      imgDown = new Array();

      // Bilder, die als Buttons verwendet werden sollen.
      // Dabei wird auch die Größe angegeben.
      imgOut[n + 0] = new Image(305,305);
      imgOut[n + 0].src = "buttons/stern_up.gif";
      imgOut[n + 1] = new Image(200,50);
      imgOut[n + 1].src = "buttons/about_up.gif";
      imgOut[n + 2] = new Image(200,50);
      imgOut[n + 2].src = "buttons/sd_up.gif";
      imgOut[n + 3] = new Image(200,50);
      imgOut[n + 3].src = "buttons/khd_up.gif";
      imgOut[n + 4] = new Image(200,50);
      imgOut[n + 4].src = "buttons/email_up.gif";
      imgOut[n + 5] = new Image(200,50);
      imgOut[n + 5].src = "buttons/sa_up.gif";
      imgOut[n + 6] = new Image(200,50);
      imgOut[n + 6].src = "buttons/wd_up.gif";

      imgOver[n + 0] = new Image(305,305);
      imgOver[n + 0].src = "buttons/stern_mo.gif";
      imgOver[n + 1] = new Image(200,50);
      imgOver[n + 1].src = "buttons/about_mo.gif";
      imgOver[n + 2] = new Image(200,50);
      imgOver[n + 2].src = "buttons/sd_mo.gif";
      imgOver[n + 3] = new Image(200,50);
      imgOver[n + 3].src = "buttons/khd_mo.gif";
      imgOver[n + 4] = new Image(200,50);
      imgOver[n + 4].src = "buttons/email_mo.gif";
      imgOver[n + 5] = new Image(200,50);
      imgOver[n + 5].src = "buttons/sa_mo.gif";
      imgOver[n + 6] = new Image(200,50);
      imgOver[n + 6].src = "buttons/wd_mo.gif";

      imgDown[n + 0] = new Image(305,305);
      imgDown[n + 0].src = "buttons/stern_dn.gif";
      imgDown[n + 1] = new Image(200,50);
      imgDown[n + 1].src = "buttons/about_dn.gif";
      imgDown[n + 2] = new Image(200,50);
      imgDown[n + 2].src = "buttons/sd_dn.gif";
      imgDown[n + 3] = new Image(200,50);
      imgDown[n + 3].src = "buttons/khd_dn.gif";
      imgDown[n + 4] = new Image(200,50);
      imgDown[n + 4].src = "buttons/email_dn.gif";
      imgDown[n + 5] = new Image(200,50);
      imgDown[n + 5].src = "buttons/sa_dn.gif";
      imgDown[n + 6] = new Image(200,50);
      imgDown[n + 6].src = "buttons/wd_dn.gif";
    };