menuHover = function(nav) {
  var sfEls = document.getElementById(nav).getElementsByTagName("li");
  for (var i=0; i<sfEls.length; i++) {
    sfEls[i].onmouseover=function() {
      this.className+=" sfhover";
    }
    sfEls[i].onmouseout=function() {
      this.className=this.className.replace(new RegExp("\\s?sfhover\\b"), "");
    }
  }

  var listItem = document.getElementById(nav).getElementsByTagName('ul');
  for(var i=0;i<listItem.length;i++) {
    listItem[i].onmouseover=function() {
      var changeStyle = this.parentNode.getElementsByTagName('a');
      changeStyle[0].className+=" active";
    }

    listItem[i].onmouseout=function() {
      var changeStyle = this.parentNode.getElementsByTagName('a');
      changeStyle[0].className=this.className.replace(new RegExp("\\s?active\\b"), "");
    }
  }
}

function addEvent( obj, type, fn ) {
  if ( obj.attachEvent ) {
    obj['e'+type+fn] = fn;
    obj[type+fn] = function(){obj['e'+type+fn]( window.event );}
    obj.attachEvent( 'on'+type, obj[type+fn] );
  } else
    obj.addEventListener( type, fn, false );
  }
function removeEvent( obj, type, fn ) {
  if ( obj.detachEvent ) {
  obj.detachEvent( 'on'+type, obj[type+fn] );
  obj[type+fn] = null;
  } else
    obj.removeEventListener( type, fn, false );
  }

addEvent(window, 'load', function () { menuHover('menu'); });