var timeout    = 1000;
var closetimer = 0;
var ddmenuitem = 0;

function navigation_open()
{  navigation_canceltimer();
   navigation_close();
   ddmenuitem = $(this).find('ul').css('visibility', 'visible');}

function navigation_close()
{  if(ddmenuitem) ddmenuitem.css('visibility', 'hidden');}

function navigation_timer()
{  closetimer = window.setTimeout(navigation_close, timeout);}

function navigation_canceltimer()
{  if(closetimer)
   {  window.clearTimeout(closetimer);
      closetimer = null;}}

$(document).ready(function(){ 
  $("#navigation > li").bind("mouseover", navigation_open)
  $("#navigation > li").bind("mouseout",  navigation_timer)
});

document.onclick = navigation_close;