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

function jsddm_open()
{  jsddm_canceltimer();
   jsddm_close();
   ddmenuitem = $(this).children('ul').first().css('visibility', 'visible');
   if(ddmenuitem.parent().position() != null)
    ddmenuitem.css("left", ddmenuitem.parent().position().left + (ddmenuitem.parent().width() * .5) + ((ddmenuitem.innerWidth() / 2) * -1));
   
   
}

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

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

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

$(document).ready(function()
{  $('#mainNavMenu > li').bind('mouseover', jsddm_open)
   $('#mainNavMenu > li').bind('mouseout',  jsddm_timer)});

document.onclick = jsddm_close;