Sitewide feed for latest comments: How to customize the output?

Hi, this is my first post to this Premium forum. I was playing around with WPMU since 1.1 just to learn how it works and decided to start something now. I´m using latest version, and with the sitewide feed plugin i can pull off latest comments very easily and with object cache, without too much usage (i belive)

The thing is that the feed title is "By author" and is kinda misleading. So i´d like to make it "By Author on Post", so it´s a bit more relevant and i can also use it with fetch_rss and get an output "By Author on Post at Date: Summary".

This is the default code:

<title>By <?php comment_author_rss() ?></title>

I tried adding:

on <?php the_title_rss() ?>

but it wont output the post title.

Any idea on how to implement this?