CVS fixes this bug:
dilvish-dan> cvs commit ../ChangeLog mhn.defaults.sh
danh@mhost.com's password:
Warning: Remote host denied X11 forwarding, perhaps xauth program could not be run on the server side.
cvs: lock.c:179: lock_name: Assertion `*short_repos++ == '/'' failed.
Terminated with fatal signal 6
cvs commit: saving log message in /tmp/cvslIx_yb