VC barfs on reversion if locked

[Marshall, Simon]

In GNU Emacs 21.2.92.1 (sparc-sun-solaris2.8, GNU/LessTif Version 2.1
Release 0.93.36)
 of 2002-11-05 on airwolf
configured using `configure  --prefix=/rvcarma/marshals/slash/usr/local
--x-includes=/usr/openwin/include:/rvcarma/marshals/slash/usr/local/incl
ude:/rvcarma/marshals/slash/usr/local/include/X11
--x-libraries=/usr/openwin/lib:/rvcarma/marshals/slash/usr/local/lib:/rv
carma/marshals/slash/usr/local/lib/X11 --with-x-toolkit=motif'
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: en_GB.ISO8859-1
  value of $LC_CTYPE: en_GB.ISO8859-1
  value of $LC_MESSAGES: C
  value of $LC_MONETARY: en_GB.ISO8859-1
  value of $LC_NUMERIC: en_GB.ISO8859-1
  value of $LC_TIME: en_GB.ISO8859-1
  value of $LANG: nil
  locale-coding-system: iso-latin-1
  default-enable-multibyte-characters: t

This isn't new to this pretest...

Visit a file under VC (RCS) where someone else already has the lock on
the file.
You want to make a quick modification but don't want the lock, so you
mouse-3 in the modeline to make it not read-only.
After you have finished, try to C-x v u to revert to the version in RCS.
Say yes to discard your changes.
VC barfs and pops up a window:

RCS/carval.cpp,v  -->  carval.cpp
co: RCS/carval.cpp,v: revision 2.16 locked by muffettm; use co -r or rcs
-u

and the checkout fails.

It should checkout the file.  Thanks, Simon.