// Accessibility links
openclose = function() {
  if(document.getElementById && document.getElementById('list')) {
    var list=document.getElementById('list');	
		// onclick version
    var button=document.getElementById('open_button');
    button.onclick=function() { 
      if (list.className=='opened') {
      	list.className='closed';
      } else {
      	list.className='opened';
      }
    }	
		// onmouseover version
		list.onmouseover = function() {
			list.className='opened';
		}
		list.onmouseout = function() {
			list.className='closed';
		}
		list.className='closed';
  }
}
// events onload
function addLoadEvent(func) {
  if (window.addEventListener) 
    window.addEventListener("load", func, false);
  else if (window.attachEvent) 
    window.attachEvent("onload", func);
}

addLoadEvent(openclose);