You don't need Access to set up an ODBC DSN to a .mdb file. A plain Windows (at least Windows 2000) install is enough.
in reply to MS Access and Perl?
Set up the DSN then use DBD::ODBC. At that point you can either use Activestate on the Windows box to connect to PostgreSQL on the remote machine or you can use DBI::ProxyServer and DBD::Proxy to connect from the *nix box back to the Windows box.
The former will probably require a little less work. I'd use the later if I needed ongoing access to the data in the .mdb and I wanted to keep my Perl all on the *nix box.
Update: To be clear, Activestate on the Windows machine is needed for either of these solutions...