Need immediate help with install

I am installing postgres 6.4 on my Solaris 2.5.1 machine. I get it to make and install fine. I run
the initdb script and it seems to complete without any problems. Here is the output from initdb

We are initializing the database system with username sdbm (uid=1030).
This user will own all the files and must also own the server process.

Creating Postgres database system directory /vol3/postgresql-6.4-solaris/data
Creating Postgres database system directory /vol3/postgresql-6.4-solaris/data/base
Creating template database in /vol3/postgresql-6.4-solaris/data/base/template1
Creating global classes in /vol3/postgresql-6.4-solaris/data/base
Adding template1 database to pg_database...
Vacuuming template1
Creating public pg_user view
Creating view pg_rules
Creating view pg_views
Creating view pg_tables
Creating view pg_indexes
Loading pg_description

This all looks fine. I start the postmaster process without any problems. Next when I try to do a
createdb as the postgres superuser I get the following:
> createdb test
Connection to database 'template1' failed.
User authentication failed
createdb: database creation failed on test.

Any idea why this is happening? I am lost. I had version 6.3.2 installed previously and started to
get the same type of errors. I thought upgrading would help. I have made sure all my paths were
correct and that no other postmasters were running.
Any help would be great!
Thanks
---------
Chris Williams
Sterling Software
Rome, New York
Phone: (315) 336-0500
Email: chris_d_williams(at)sterling(dot)com