>> cvs tag -d DRUPAL-4-5 file(s)
>
> I tried doing this but got the following message: "cvs tag: Not removing branch tag
> `DRUPAL-4-5' from /cvs/drupal-contrib/contributions/modules/interwiki/CREDITS.txt,v'."
Perhaps this file is new and not previously tagged?
Do a:
cvs log CREDITS.txt
and see if there are any tags under 'symbolic names'.