function current() {
    var anchors = document.getElementsByTagName('a');
    for (var i = 0, l = anchors.length; i < l; i++) {
        var a = anchors[i];
        if (a.href.indexOf(window.location.pathname+window.location.search) != -1) {
            a.className += " current";
            return;
        }
    }
}

if (window.attachEvent)
    window.attachEvent('onload', current)
else
    window.addEventListener('load', current, false)