function addsel() {
  var a = document.getElementsByTagName("A"), h;
  var url = relpath(window.location.href.split("#")[0]);
  for (var i=0; i<a.length; i++) {
    h = relpath(a[i].href);
    if (h == url || (h.length > 1 && h == url.substr(0, h.length))) {
      a[i].className += ' sel';
    }
  }
}
function relpath(url) {
  if (url[0] == '/') return url;
  return url.replace(/^http:\/\/[^\/]+/g, '');
}

window.onload = addsel;