$(document).ready(function () {   
      
    $('#nav2 li').hover(  
        function () {  
            //show its submenu  
			$(this).css("z-index", "900");
				
            $('ul', this).slideDown(100);  
  
        },   
        function () {  
            //hide its submenu  
			$(this).css("z-index", "1");
            $('ul', this).slideUp(100);           
        }  
    );  
      
});