var odiv = "";
var menus = {};

$(function() { 
	$("#nav li").each(function(i) {		
		sdiv = $(this).find("div").attr("id");
		if ( sdiv ) {
			menus[i] = sdiv
			$(this).mouseover(function(){
				toggle_menu ( menus[i] );		 
			});
			$(this).mouseout(function(){
				toggle_menu ( "z" );
			});
			$(this).find("div").mouseout(function(){
				toggle_menu ( "z" );
			});
		} else { // There is a sub menu
			$(this).mouseover(function(){
				toggle_menu ( "z" );
			});
		}
		
	});
		   
});

function  toggle_menu ( menu ) {
		menu = "#" + menu;
		if (odiv != "") { $(odiv).css("visibility","hidden"); }
		$(menu).css("visibility","visible");
		
		odiv = menu;	
}