if(/msie 6\.0/i.test(navigator.userAgent)) {
    hoverState = function() {
        els = document.getElementById('nav').getElementsByTagName('li');
        for(var i = 0, il = els.length; i < il; i++) {
            els[i].onmouseover = function() {
                this.className += " hover";
            };
            
            els[i].onmouseout = function() {
                this.className = this.className.replace(new RegExp(" hover\\b"), "");
            };
        }
    };
    window.attachEvent("onload", hoverState);
}