Problems getting postgress started on RH Linux 5.1

Hi there

I am having a problem with Postres initial setup and would REALLY appreciate
your help. I'm not sure if I have screwed up a config file or maybe not set
something necessary in a config file. I set RH 5.1 linux to use Postgress on
startup and have had difficulty interpreting the actual bits of the docs in
/urs/doc/... on how to actually get the thing configured. On trying to use the
createdb command I get the message:

Connection to database 'template1' failed.
ERROR: cannot read block 0 of pg_shadow
createdb: database creation failed on ian.

I have set PGDATA and PGLIB env variables well enough to be able to run the
initdb command. I would (again) REALLY appreciate your help with this initial
setup. I have used mSQL at home and at school both as an administrator and user
and am comfortable doing both. I am just a bit stumped at the moment.

--
Ian A. Marsman
ianm(at)niagara(dot)com