How to configure postgresql so it accepts login+password auth?

It is probably a good idea to leave the "postgres" user with ident authentication. By default I believe Ubuntu uses the "postgres" user to perform upgrades, backups, etc, and that requires that it is able to login without a specified password.

I recommend creating another user (probably with your own username) and giving it admin privileges as well. Then you can use that user with passwords on local connections.

Here is what the relevant parts of my pg_hba.conf look like:

# allow postgres user to use "ident" authentication on Unix sockets# (as per recent comments, omit "sameuser" if on postgres 8.4 or later)local   all   postgres                         ident sameuser# allow all other users to use "md5" authentication on Unix socketslocal   all   all                              md5# for users connected via local IPv4 or IPv6 connections, always require md5host    all   all        127.0.0.1/32          md5host    all   all        ::1/128               md5

Also note that psql -U postgres password will not do what you want. The password should never be specified on the commandline. That will try to login as user "postgres" to a database named "password".

You should use psql -U postgres myapp instead. Postgres will automatically prompt you for a password, if it is configured properly to require one.

In case we want the password be filled-in automatically, place it in $HOME/.pgpass file

I think your pg_ident.conf file is misconfigured. Also, have you tried

psql -U postgres -W

Another thing that can cause this is expired credentials. I don't think this happened in version 8, but in version 9 when you create a new role in pgadmin, it is created in an expired state and you need to change or clear the role's expiration date before you will be able to login with it.