Invalid postmaster.pid

I'm a new Linux user, RH6.0. PostgreSQL-6.4.2-3. The package was
installed when I installed the RH cd.

This is the error message I get on startup: (linuxconf log)

Executing: /etc/rc.d/rc5.d/S85postgesql start
* /usr/bin/postmaster does not find the database system. Expected
to find it in the PGDATA directory "/var/lib/pgsql" , but unable to open

the
file with pathname "/var/lib/pgsql/base/template1/pg_class".
*
* no data directory -- can not proceed
> starting postgresql service: postmaster []

Any help you can provide me would be appreciated. I just assumed that
the RPM install would have created all the necessary files and
directories I needed.

Thanks

Tim Potier