Opening a PG filesystem db backup on a new server

I'm setting up a staging / test installation of a running application, and
have copied the PG data directory (/var/pgsql/data) to the new machine via a
tarball and replaced the data directory created with the initdb run when PG
was installed on the new server.

Is anything special required to get a new installation of Postgres to open a
database created on another server? The postmaster seems to start OK, but my
OpenACS-based application is not starting as it should. The problem could be
with AOLserver or other factors, but I want to check that I'm doing the
right thing with the database startup.

I'm starting postgres by running the following command as user postgres:

/usr/local/pgsql/bin/pg_ctl -D /var/pgsql/data -l server.log start

Postgres version on the original server is 7.2.1, the new server has 7.2.4
installed. Both machines are running Debian 3.0, with the 2.4.18 kernel.

Thanks for any insight,

Dave De Graff