Fail initdb en PostgreSQL V 7.02

Hi all,

Case 1
++++++++
I have installed PostgreSQL 7.02, and  my all the enviroment
variables are initializated, however when i initialized the Data Base with
get the next message error

bash$ initdb

We are initializing the database system with username postgres (uid=26).
This user will own all the files and must also own the server process.

Creating template database in /var/pgsql/data/base/template1
ERROR:  Error: unknown type 'oidvector'.

ERROR:  Error: unknown type 'oidvector'.

        syntax error 12 : parse errorinitdb: could not create template
database
initdb: cleaning up by wiping out /var/pgsql/data/base/template1

Case 2
++++++++
Before I had installed postgresql version 6.5.3, but I to load a table
with 2.800,000 rows, when I created the index of table, send me the
following message error:

pqReadData() -- backend closed the channel
unexpectedly.
        This probably means the backend terminated abnormally before or
while processing the request.
pqReadData() -- backend closed the channel unexpectedly.
        This probably means the backend terminated abnormally before or
while processing the request.

I thouth that my version was the problem, but I believe that my table is
too large, how can I do with this data base?

My operate system is : Red Har version 6.2, the machine is Pentiumm II 600
MHZ, HD 10 GB and 128 RAM memory.

I need sugestions,

Thanks in Advance.

Regards,
"La Vida"