window.onload = function() {
  setLinks();
}

function setLinks() {
  if (!document.getElementsByTagName) return false;
  var links = document.getElementsByTagName("a");
  if (links.length == 0) return false;
  for (var i = 0; i < links.length; i++) {
    var relation = links[i].getAttribute("rel");
    if (relation == "external") {
      links[i].onclick = function() {
        return !window.open(this.href);
      }
    }     
  }
}

function checkMainSearchForm() {
   if (document.getElementById('mainsearch').q.value == "") {
      alert('Please enter some words.');
      document.getElementById('mainsearch').q.focus();
      return false;
      }
}