did you ever get past your problem? I saw a post in a search, but
never really saw the solution. original link I found:
http://archives.postgresql.org/pgsql-admin/2005-07/msg00166.php
I (believe) the correct solution for postgres on gentoo linux is:
mkdir /var/lib/postgresql
chown postgres /var/lib/postgresql
su postgres -c "initdb -D /var/lib/postgresql/data/"
ls /var/lib/postgresql/data/
/etc/init.d/postgresql start
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