Wrong RSS URL in web statistics log

We have, not at least by reading useful interventions in this forum, been able to set up a WordPress blog on our site, We have one problem, though. In our Urchin statistics log we are recieving thousands of hits on non-existing URLs.

In short, someone are adding the phrase “feed/index.html” to the end of the correct post URL, for instance like this:

correct URL:
http://www.pandia.com/sew/63-msn-adds-operators-for-rss-search.html

Incorrect URL:
http://www.pandia.com/sew/63-msn-adds-operators-for-rss-search.html/feed/index.html

There are seveal entires in the log that may explain this, like for instance:
84.209.242.157 – – [06/Sep/2005:20:11:12 +0000] “GET /sew/61-chirac-takes-on-google.html/feed/ HTTP/1.1” 304 0 “-” “NewzCrawler/1.7 (compatible; MSIE 6.00; Newz Crawler 1.7; http://www.newzcrawler.com/ )”

213.85.81.13 – – [06/Sep/2005:20:14:37 +0000] “GET /sew/55-new-version-of-google-desktop-search.html/feed/ HTTP/1.1” 304 0 “-” “Mozilla/5.0 (compatible; MSIE 6.00; Windows 98)”

Does anyone know why newsreaders and browsers should add /feed/ to the URL?

We have announced the following variants of the RSS URLs:

http://www.pandia.com/sew/wp-rss2.php
http://www.pandia.com/sew/wp-rss.php
http://www.pandia.com/sew/wp-atom.php
Info at: http://www.pandia.com/info/rss.html

In the header the URL is listed as <link rel=”alternate” type=”application/rss+xml” title=”RSS” href=”http://www.pandia.com/sew/wp-rss2.php”&gt; on the non-Wordpress pages and <link rel=”alternate” type=”application/rss+xml” title=”RSS 2.0″ href=”http://www.pandia.com/sew/feed/&#8221; />
<link rel=”alternate” type=”text/xml” title=”RSS .92″ href=”http://www.pandia.com/sew/feed/rss/&#8221; />
<link rel=”alternate” type=”application/atom+xml” title=”Atom 0.3″ href=”http://www.pandia.com/sew/feed/atom/&#8221; /> on the WordPress generated pages.

We would be grateful for any comment that might point us in the right direction.