var DropdownMenu = new Class({
    initialize: function(element)
    {
        $A($(element).childNodes).each(function(el)
        {
            if(el.nodeName.toLowerCase() == 'li')
            {
                $A($(el).childNodes).each(function(el2)
                {
                    if(el2.nodeName.toLowerCase() == 'ul')
                    {
                        $(el2).setStyle('display', 'none');
                        
                        el.addEvent('mouseover', function()
                        {
                            el2.setStyle('display', 'block');
                            return false;
                        });

                        el.addEvent('mouseout', function()
                        {
                            el2.setStyle('display', 'none');
                        });
                        new DropdownMenu(el2);
                    }
                });
            }
        });
        return this;
    }
});