I'm not sure how you've got your setup but this is what im doing and our users are pretty happy. They just have to communicate well.
in loginfo i have this:
ALL /bin/mail -s '$USER modified REPOSITORY %{sv}'
CVSUSERSMAILGROUP@domain.com
since we use a managed passwd file for each repository they all get an email everytime someone commits a file.
i suppose if you can find the correct CVSROOT/file that could at least inform the masses when someone does this might do. Peer pressure keeps peeps from doing stupid stuff. LOL
I was reading something a little bit ago about someone who was running a script through the commit function but there were no links to what he had done and was very vague.