Why Css? Why?!

Lately css has been giving me biggg time hassles. I have some links inside a div. I want them to be different from all other links outside that div. Easy, right? So I do this:

#menu_holder a:link,a:visited {
 text-decoration: none;
	margin-right: 20px;
	padding: 5px;
	color:#FFFFFF;
	font-weight: bold;
}
#menu_holder a:hover {
	text-decoration: underline;
	background-color: #006599;
}

I works, but after I click a link outside that div, after maybe two secs it changes to be just like the #menu_holder a:link,a:visited! And it’s not even inside it!

What’s up with this???!!! Maybe it’s just FF3?

Much appreciated, motionman95.