FW: 2 instances

Hello.

I would like to run 2 instances of postgresql with 2 different
data-directories: dir-a en dir-b.

Looking trough the archives I came to the next setup:

I created this 2 different directories and 2 users each with a different
PGDATA(dir-a and dir-b) in their .profile
Using this 2 users i did twice initdb and createdb xyz with the first
user.

in postgresql.conf of the second directory I changed the port to 5433 and
also entered this port in /etc/services and started the second
postmaster, ps -f shows it is running.

If I now want to create the same database xyz in the second directory
using the second user,
the database is already there!

What am I missing?

Many thanks

Henk Sander