Hjälp med en meny

Har en meny som funkar jättebra men vill att när man klickat på något i undermenyn so skall huvudmenyn till denna vara öppen så man ser den länk man klickat på.. alltså de andra menyvalen i just den undermenyn. Denna menyn är denna: http://www.cssplay.co.uk/menus/dl-clickslide.html

<style>
#positioner {position:relative; width:150px; height:160px; z-index:100;}
#holder {position:absolute; width:150px; overflow:hidden; background:#f0f0f0;}
dl.menu {width:300px; float:left; margin:-32700px -150px 0 0; background:url(clickslide/tab1.gif) no-repeat left bottom; margin-bottom:2px;}
dl.menu a {display:block; height:30px; color:#000; font:bold 11px/28px verdana, sans-serif; text-decoration:none;}

dl.menu dt {float:left; padding:0; margin:32700px 0 0 0; position:relative; z-index:50;}
dl.menu dt a.lefta {width:120px; float:left; padding-left:10px;}
dl.menu dt a.plusa {width:20px; float:left; background:url(clickslide/down.gif) no-repeat center center;}
dl.menu dt a.plusa b {position:absolute; left:-9999px;}

dl.menu dt a.lefta:hover,
dl.menu dt a.lefta:focus,
dl.menu dt a.lefta:active {color:#c00;}

dl.menu dt a.plusa:hover {background:url(clickslide/down2.gif) no-repeat center center;}

dl.menu dt a.plusa:focus,
dl.menu dt a.plusa:active
{margin-right:1px; background:url(clickslide/down2.gif) no-repeat center center; outline:0; position:relative; left:-9999px;}

dl.menu dd {float:left; padding:30px 0 0 0; margin:-30px 0 0 0; position:relative; z-index:10; background:url(clickslide/tab3.gif) no-repeat left top;}
dl.menu dd a {background:#fff; width:140px; padding:5px 0 5px 10px; border-bottom:1px solid #ccc; font-weight:normal; line-height:17px; height:auto;}

dl.menu dd a:hover,
dl.menu dd a:focus,
dl.menu dd a:active
{margin-right:1px; color:#c00; outline:0;}
</style>

<div id="positioner">
	<div id="holder">
		<dl class="menu">
			<dt>
				<a class="lefta" href="meny.html">Startsidan</a>
			</dt>
		</dl>
		<dl class="menu">
			<dt>
				<a class="lefta" href="javascript:void();">Om Företaget</a>
				<a class="plusa" href="javascript:void();"><b>+</b></a>
			</dt>
			<dd>				
				<a href="meny.html">Historik</a>
				<a href="meny.html">Huvudinriktining</a>
				<a href="meny.html">Kontoret</a>
			</dd>
		</dl>
		<dl class="menu">
			<dt>
				<a class="lefta" href="javascript:void();">Nästa</a>
				<a class="plusa" href="javascript:void();"><b>+</b></a>
			</dt>
			<dd>				
				<a href="meny.html">Ett</a>
				<a href="meny.html">Tvä</a>
				<a href="meny.html">Tre</a>
			</dd>
		</dl>
	</div>
	<div style="clear: both;"> </div>
</div>