maintaining local repository with development done at another place.

[Chinnakrishnan]

Hi All,
i am maintaining a local repository of an application, while the
development of that takes place at another location, and they have
their own repository. whenever there is a new release from the
development they will send us a tar ball. i have to update that in the
local repository i maintain. there may be some new files, deletions,
changes etc. how do i do this. in general, how do i be in sync with
the development repository whenever there is a new release.
Thanks for your help,
Chinnakrishnan.