Import on existing repository ?

[TestMan]

Hi all,

I got the following issue :
- A customer is having a centralized CVS repository.
- We have to deliver new release source code trees into it (code is 
consistent and working).
- Development team does not have access to "checkout" of the repository 
(so no "existing" versions or diff can be found). Hence they are working 
 on their own repository.

And I need to deliver the updated "release" into the CVS. How can I do 
that with CVS ?

FYI, the first time an cvs import is perfectly working as expected, but 
second time it does not work as files that have been removed from new 
release or updated with a conflict are not "synced".

Hence, how can i do an import on an existing repository with the 
following effects :
- new files are added in the repositories
- change in files are applied to the repository (no concurent update 
from the same provider possible, so what is delivered is what should be 
exactly pushed in the repository)
- deleted files and folder are deleted in the repository
- up-to-date branch is created with BUILDXXXXXX tag key

I thought it was "easy" to do, but I am stuck on that since days and 
found no ways to do it ... so any help is welcomed ;-)

Regards,
TM