Problems with RSS and DF-Style Linked List plugin

Good morning,
I’m slowly mucking my way through teaching myself PHP, etc. via my WordPress blog. I’m using a slightly older theme (no loop.php file), but the latest version of WordPress.

My problem is this: I’ve added the DF-style Linked List plugin and it’s screwed up my RSS feed a bit. After activating the plugin, editing the theme, etc., my RSS feed titles link to the appropriate pages but append some crap onto the link so that I get a 404 error. So, if my linked list item should point to:

foo.com/example/

the actual link in the rss feed will be to

foo.com/example/http://?utm_source=rss&utm_medium=rss&utm_campaign=example

Here’s some of the actual rss feed. The whole thing is at WingsOfReason.com/feed.

<item>
<title><![CDATA[OopsieFocus]]></title>
<link><![CDATA[http://shawnblanc.net/2011/06/oopsiefocus/]]>http://?utm_source=rss&utm_medium=rss&utm_campaign=oopsiefocus</link>

So it seems apparent to me that the rss feed is getting the link and then adding that other junk with referral/campaign-type data. I can’t for the life of me figure out where that stuff comes from or even where the files are to edit it out. Can anyone help me?

Thanks in advance for your help,
Stuart the PHP/RSS/Wordpress newbie.