pg_hba.conf stuff

Hi all,

I have a server (Ubuntu 6.10 to be exact) running PostgresQL 8.1.4.

On that server I have a user account, called "ynui", and I also have a
postgres user called "ynui", they have the same password. Now the
server's IP is 192.168.0.1

My main postgres conf has in it:

listen_addresses = 'localhost,192.168.0.1'

my pg_hba.conf is:

# "local" is for Unix domain socket connections only
local all all md5
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all ::1/128 md5
# Internal network
host all all 192.168.0.0/24 md5

Now I have a client PC 192.168.0.10, it's also running Linux and the
unix account name on this machine is rob. I have the postgres client
installed on this machine and am connecting like this:

psql -h 192.168.0.1 -U ynui

Now my problem is, because the server has on it a user account "ynui"
and postgres also has a user called "ynui", with the same password, it
goes straight in, without asking for the password at all!!!

This is even though I specifically configured the "Internal network"
section in my pg_hba.conf file for "md5", and this "ynui" unix user is
actually on the server, not on the client pc. Then why does it still go
straight in from the client PC without asking for the password for the
"ynui" user?

Any ideas? is there any way to prevent this automatic login, or is the
only way to have the unix "ynui" user and postgres "ynui" user no the
server to have a different password? I would prefer them not to have
different passwords however if possible.

Any ideas? any help would be appreciated.