function toggle(id){
  ul = "ul_" + id;
  img = "img_" + id;
  ulElement  = document.getElementById(ul);
  imgElement = document.getElementById(img);
  if (ulElement){
    if (ulElement.className == 'closed'){
       ulElement.className = "open";
       imgElement.src = "images/arrow_opened.gif";
    } else {
       ulElement.className = "closed";
       imgElement.src = "images/arrow_closed.gif";
    }
  }
}

function highlight(id){
	ulElement = document.getElementById(id);
	ulElement.className = "current";
}