Initfb fails

Dear All:
I am new to linux and postgresql and Ihave a problem.

I installed the RedHat rpm packages for postgresql 6.4.3-2 and tried to
follow the intructions in chapter 4 about the installation. The problem
lies with initdb. After entering as user postrgres, from the shell (in
/usr/var/pgsql) I run:
"initdb --pglib=/usr/lib/pgsql --pgdata=data --username=postgres"

and get the following error:

"We are initializing the database system with username postgres
(uid=102).
This user will own all the files and must also own the server process.

Creating template database in data/base/template1
ERROR: cannot read block 0 of pg_variable
ERROR: cannot read block 0 of pg_variable
initdb: could not create template database
initdb: cleaning up by wiping out data/base/template1"

I cant figure out what this error means or how to fix it. Can anybody
help?

Kind thanks

Argentino

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Argentino Trombin
Finsiel SpA
Rome, Italy