function cambiaEnlacesExternos() {
  var links = document.getElementsByTagName('a');
        
  for (var i=0;i < links.length;i++) {
    if (links[i].className == 'new-window') {
      links[i].onclick = function() {
        window.open(this.href);
        return false;
      };
    }
  }
}