[Mediawiki-l] Limiting RSS output?

[Michelle]

Using the wiki RSS capability, we are syndicating our Newpages titles to our main (non-wiki) page using a 3rd-party feed service.  Unfortunately the feed has bogged down the service, and they've had to stop their crawlers from checking it for updates.  The problem appears to be a combination of some very long articles (the entire article appears in the RSS feed description block) and the large number of articles that are being output to the feed.  

Is there a way to restrict the RSS output so as not to have the article contents included, and/or a way to restrict the number of articles that are output?  If it's not settable, a suggested hack would be much appreciated.  I've looked at Feed.php but I have no idea how to modify it.  We are running 1.3.7.

Thanks,
Michelle