Me again . . .

On a site I'm developing there's a sidebar of links on the right. The first section is like this:
HTML Code:
<div id="rightColumn">
<div class="inside">
<div class="vnav">
	<h3>About Us</h3>
	<ul><li><a 
		href="history.asp">History and Purpose</a></li><li><a 
		href="members.asp">Members of the Group</a></li><li><a 
		href="http://www.cbcofsmyrna.com/">Calvary Baptist Church</a></li></ul>
</div>
<div class="vnav">
...
I'm using ASP to determine which section of the site someone is on and highlight the appropriate sidebar link. For example, if they're at history.asp, I want the first <li> to be a different color.

Problem is, no matter how I apply the CSS, I can't seem to get it to override the CSS that's inherited:
HTML Code:
#rightColumn .vnav ul li a:hover, .vnav ul li a:hover
{
	background-color: #248;
	color: #fff;
}
#rightColumn .vnav ul li a
{
	background-color: #bcd;
	color: #336;
}
I've changed the id and class for the <li>, then written all sorts of CSS for that particular id or class, and every time I still get the colors listed above.

What am I missing?