RSS feeds per category

I’ve done a search on the forum’s and I’ve found about the wp_list_cats business but it isn’t quite what I want. Basically, I want that little orange RSS icon in Firefox/Flock to link to RSS feed of the category the user is viewing.

I assume I need to change the “href” but I’m not sure what it needs to be changed to.

<link rel="alternate" type="application/rss+xml" title="<?php bloginfo('name'); ?> RSS Feed" href="<?php bloginfo('rss2_url'); ?>" />

Hope someone can help!