can't create database

on one of the AIX4.3.3, 
the 7.1.3 pgsql is installed by root on the system, 
then I tried to install
7.3.1/or 7.3.2 under another non-root user,
I can run make, make check, make install,
postmaster can start without errors, but when
I try to createdb, here're some errors -

createdb emrxdbs
ERROR:  'autocommit' is not a valid option name
createdb: database creation failed

then I issued, 
postgre7.3.2>psql template1
ERROR:  parser: parse error at or near "."
Welcome to psql 7.3.2, the PostgreSQL interactive terminal.

Type:  \copyright for distribution terms      \h for help with SQL commands      \? for help on internal slash commands
    \g or terminate with semicolon to execute query      \q to quit
 

template1=> select version();                         version                           
------------------------------------------------------------PostgreSQL 7.1.3 on powerpc-ibm-aix4.3.3.0, compiled by cc
(1 row)

template1=> 

it picks the older version and always having a parser error!!

Any hints?

thanks.

johnl