var Menu = function(el)
{
	if (document.all && el.currentStyle)
	{
		this.initList(el, 0)
	}
}

Menu.prototype =
{
	initList: function(node, level)
	{
		do
		{
			switch (node.tagName)
			{
				case 'LI':
					this.initNode(node, level)
					break
				
				case 'UL':
					level++
					break
			}
			if (node.firstChild)
			{
				this.initList(node.firstChild, level)
			}
		}
		while (node = node.nextSibling)
	
		level--
	},

	initNode: function(node, level)
	{
		this.whiteSpace(node)
		var el = node;
		
		do
		{
			if (el.className && el.className.search('on') != -1)
			{
				return;
			}
			//document.getElementById('debug1').innerHTML += el.tagName + '<br/>';
		}
		while ((el = el.parentNode));
		
		//document.getElementById('debug1').innerHTML += el.tagName + '<br/>';
		
		node.onmouseover = function()
		{
			if (this.lastChild && this.lastChild.tagName == 'UL')
			{
				this.lastChild.style.display = 'block'
			}
		}
	
		node.onmouseout = function()
		{
			if (this.lastChild && this.lastChild.tagName == 'UL')
			{
				this.lastChild.style.display = ''
			}
		}
	},

	whiteSpace: function(el)
	{
		var i = 0
	
		do
		{
			if (el.childNodes[i].nodeType == 3 && !/\S/.test(el.childNodes[i].nodeValue))
			{ el.removeChild(el.childNodes[i]) }
		}
		while (el.childNodes[++i])
	
		return el
	}
}
/*
window.onload = function()
{
	new Menu(document.getElementById('mainNav'));
}
*/