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

function mopen(id) {	
  mcancelclosetime();
  if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';
  ddmenuitem = document.getElementById(id);
  ddmenuitem.style.visibility = 'visible';
}

function mclose() {
  if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';
}

function mclosetime() {
  closetimer = window.setTimeout(mclose, timeout);
}


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

document.onclick = mclose;