local cvs server : can't check out to specific directory

[Singer]

Hi all
I want to create a local CVS repository to maintain my own project
developing.
My enviroment is Windows XP + WinCVS1.2
My working directory is as the following:

Root
     Dir1
     Dir2
         Dir21
         Dir22
     Dir3
         Dir31
         Dir32

I only want to maintain "Dir21" and "Dir31". I use the following
procedure.

1. rename "Root" to "_Root"
2. Make a copy of "_Root" with name "ROOT"
3. remove "Dir1" "Dir22" and "Dir32" in the new "ROOT"
4. import this new root to local repsitory
5. Delete new "ROOT" and restore the original one.

After that I want to checkout modules to the original "ROOT", but I
meet problems. CVS give such info:

///////////////////////////////////////////////////////////////////////////
cvs checkout: Updating ROOT
? ROOT/Dir1
? ROOT/Dir2
? ROOT/Dir3
*****CVS exited normally with code 0*****
//////////////////////////////////////////////////////////////////////////

But if I check out this module to directory other than "ROOT", opeation
can be successful.

Acturally I want to work on "ROOT" directory and let cvs maintaining my
working status, however, seems wincvs prevented me from doing so.

Can anyone help me out?