Trying using Postgresql on FreeBSD

Hi,
I'm running FreeBSD 2.8 and I downloaded and installed PostgreSQL 6.4. I
can start postmaster (-i), but when I try to run createdb, to create a
database, I get a output saying:
Connection to database 'template1' failed.
pqReadData() --backend closed the channel unexpectedly.
This probably means the backend terminated abnormally before or while
processing the request.
createdb: database creation failed on userxx

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Allan Cardech de Lemos                         e-mail: allan@ufrrj.br
Univ. Federal Rural do Rio de Janeiro          http://www.ufrrj.br
Coordenadoria de Informatica                   Phone (+55) (21) 6821349
Rodovia Br. 465 Km 7 - Seropedica              Fax   (+55) (21) 6821070
CEP 23890-000
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