suspected bug report or feature request - tagging a sparse directory

Hi,

I have a problem with tagging a sparse directory.

Suppose I have this structure:

myproj
  dirA
       ...
  dirB
       ...

I want user A to work on dirA, and user B - on dirB.
But both are contributing to the same release-candidate, let's call it rel_X.
(the idea is that integrator would be taking whole myproj using
release-candidate tag rel_X)

So, user A builds sparse working copy of myproj

% svn co $SVNROOT/myproj -–depth empty myproj
% svn update -–depth infinity myproj/dirA

 .. modifies it in some way and tries to tag:

% svn mkdir $SVNROOT/tags/rel_X
% svn copy myproj $SVNROOT/tags/rel_X/ -m “tagging part A of myproj
for the next integration”

The problem that we see is SVN for some reason also copies dirB under
$SVNROOT/branches/rel_X !!
% svn ls $SVNROOT/tags/rel_X/myproj
dirA
dirB <- this should not be there !

my SVN version is 1.6.2 (r37639)

I was under impression that svn copy WC -> URL should take whatever I
have in my WC,
and ONLY that, similar to unix copy.
The whole point of this mode (WC -> URL) it to remember (tag) any
weird combination of versions/components
that I've built in my WC. So why copy the rest of the world ? If
that's not a bug but feature, would it be possible
to have a switch to copy command that would behave as I described ?

thanks !

--
Stas Cherkassky
email:   scherkas_at_gmail.com
phone:  +972-54-4261959