When a file has been deleted, on subsequent applies of
the change that deleted the file, we get CVS conflicts.
From what I can see, the "cvs update" of the file in
question is stupidly pulling the file out of the Attic,
and doing header/revison replacement, and comparing
with the existing file, before actually deleting it.
It sees the revision difference as a problem and thus -
CONFLICT!
Note that this problem only manifests with
NoClobber=false. Since changing this setting manages
to work around the problem, I'd say this is fairly low
priority.