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

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

function jsddm_close()
{  
	if(ddmenuitem) ddmenuitem.css('display', 'none');
}

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

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

jQuery('div#top header nav ul > li').bind('mouseover', jsddm_open);
jQuery('div#top header nav ul li ul').bind('mouseout',  jsddm_timer);