function containsDOM (container, containee) 
{
	var isParent = false;

	do 
	{
		if ((isParent = container == containee))
	{
	break;
	}
		containee = containee.parentNode;
	}
	while (containee != null);

	return isParent;
}


function checkMouseEnter (element, evt) 
{
	var isMouseEnter;
	
	if (element.contains && evt.fromElement) 
	{
		isMouseEnter = !element.contains(evt.fromElement);
	}
	else if (evt.relatedTarget) 
	{
		isMouseEnter = !containsDOM(element, evt.relatedTarget);
	}
	
	return isMouseEnter;
}


function checkMouseLeave (element, evt) 
{
	var isMouseLeave;
	
	if (element.contains && evt.toElement) 
	{
		isMouseLeave = !element.contains(evt.toElement);
	}
	else if (evt.relatedTarget) 
	{
		isMouseLeave = !containsDOM(element, evt.relatedTarget);
	}
	
	return isMouseLeave;
}


function showSubMenu(submenuId)
{
	var submenu = document.getElementById(submenuId); 
	submenu.style.display = "block";
}


function hideSubMenu(submenudId)
{
	var submenu = document.getElementById(submenudId); 
	submenu.style.display = "none";
}