navigation background arrow disappears on drop downs

Why do the arrows only appear on the very first button in a drop down series but not any of the other ones?  

For example, under Programs/Schedules on the main nav bar, Dance displays the arrows but none of the ones below Dance shows the arrow.

http://nsitedesigns.com/nsitedesigns/ymca/test.html
http://nsitedesigns.com/nsitedesigns/ymca/test.css

/* ............ NAVIAGTION ................ */

#main_stage #sidebar1 ul#nav li:hover ul, li.over ul { display: block; }

ul#nav {
	width: 200px; /* Width of Menu Items */
	float:left;
	position:relative;
	padding-top:20px; /*pushes nav bar down the page*/
	
	} 

ul#nav li {
	line-height:1.4em;
	list-style: none;
position:relative;
	}
	
	ul#nav li.last {
	margin-bottom:20px;
	}
	
/* drop downs */
ul#nav li ul {
	position: absolute;
	left: 132px;/* position of drop downs next to main nav bar */
	top: 0;
	display: none;
	width:150px;
	}

/* Menu Items */
ul#nav li a {
	background: #fff; /* IE6 Bug */
	display: block;
text-decoration:underline;
	color: #0d4c76;
	padding: 4px 0px 4px 25px;
	font-size:.9em;
	font-weight:bold;
	font-family:Verdana, Geneva, sans-serif;

	}

/* Fix IE. Hide from IE Mac /
* html ul#nav li { float: left; height: 1%; }

 html ul#nav li a { height: 1%; }*/



/* Hover Styles */
ul#nav li a:hover {
	color: #0d4c76;
	background-color:#FF9; 
	background-image:url(img/arrows.gif);
	background-repeat:no-repeat;
	background-position:left center;

} 
	

/* Sub Menu Styles */

li ul li a { 
padding: 7px; 
margin-left:2px;
background-color:#FF9;} 
		


#main_stage ul#nav li:hover ul, li.over ul { display: block; }



li#last a {
	margin-bottom:20px;
}

Select allOpen in new window