$.fn.navi = function(arguments) {
	arguments = $.extend({
		speed : 50000
	}, arguments);
	
	function openSubmenu(el) {
		el.children('ul').fadeIn(arguments.speed);
	}
	
	function hideSubmenu(el) {
		el.children('ul').fadeOut(arguments.speed);
	}
	
	$(this).hover(
		function(){
			if ($(this).css('opacity') != 0 ) {
				$(this).stop();	
			}
			openSubmenu($(this));
		},
		function(){
			hideSubmenu($(this));
		}
	);
}