Custom title in RSS (Category: Title)

Hi.

I am the editor of Russian blog about tv shows ZigaZaga.tv. We are writing about many different shows and on our index page the titles of the post look like this:

• Desperate Housewives: The new season
• The Office: Begining of teh 5th season

The code is something like <?php the_category(' '); ?>: <?php the_title(); ?>.

But of course in the RSS feed the titles are:

• The new season
• Begining of the 5th season

We need our rss feed to be more informative, so we want to have titles in RSS like Category: Title.

I’ve tried to change code in /wp-incude/feed-rss2.php. But when i put <?php the_category_rss() ?> or <?php the_category(' '); ?> inside <title></title> it does not show category in RSS.

What should i do? Maybe there is some plugin that could solve this problem?

I also tried Yahoo! Pipes but this service doesn’t work for me.