var timeout    = 500;
var closetimer = 0;
var ddmenuitem = 0;

function jsddm_open()
{  jsddm_canceltimer();
   jsddm_close();
   ddmenuitem = $(this).find('ul').css('visibility', 'visible');
}

function jsddm_close()
{  if(ddmenuitem) ddmenuitem.css('visibility', 'hidden');
{  $('#main-nav > li').removeClass( 'hover' );}}

function jsddm_timer()
{  closetimer = window.setTimeout(jsddm_close, timeout);}

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

function jsddm_keephover()
{  $( this ).addClass( 'hover' );}

$(document).ready(function()
{  $('ul.sf-menu > li').bind('mouseover', jsddm_open)
   $('ul.sf-menu > li').bind('mouseout',  jsddm_timer)
   $('ul.sf-menu > li').bind('mouseover', jsddm_keephover)
});

document.onclick = jsddm_close;