In Wordpress 2.1+, fixes Page feeds so they show Page content instead of an empty comments feed.
The bug didn't exist in Wordpress 2.0 and was supposed to be fixed in 2.2 (??) but I still see it in 2.2.
It just tells Wordpress to stop using the RSS comments template for Page feeds.
You can view a feed for an existing Page by appending
&feed=feed to a Page URI (see Finding Your Feed URL), e.g. (replace page with the page name):