Argh... cvs admin -b

[Josh Baudhuin]

Argh... whenever you check something into the main trunk, after having
marked the default branch, the default branch setting in the archive
file gets lost.

I.e., say you have a file with branch 13.9.2 and head revision 13.11.
        cvs admin -bFOO foo.cpp

Now when you say
        % cvs log -h foo.cpp
you see:
        RCS file: ...
        Working file: foo.cpp
        head: 13.11
        branch: 13.9.2
        locks: strict
                .
                .
                .

However, if I commit a new revision on the main trunk
        cvs update -A foo.cpp   # should get head revision on branch
13.9.2
        cvs update -r13 foo.cpp # should get head revision on main trunk
        cvs edit foo.cpp                # let's tweak this file:
        echo "huzzah!" >> foo.cpp
        cvs commit -m"huh?" foo.cpp     # should create revision 13.12

but alas, now
        % cvs log -h foo.cpp
reveals
        RCS file: ...
        Working file: foo.cpp
        head: 13.12
        branch: 
        locks: strict
                .
                .
                .

i.e., it's lost the branch! D'oh!

What's worse is if you set the default branch, update your sandbox, and
try to commit a revision to it (i.e., sans sticky tags for the branch
because it's the default branch after all), it completely ignores the
default branch and promotes the new revision to the head of the main
trunk! (And loses the default branch setting, of course!)

Is this expected behavior? Is it a bug?