Connection problem

I'm having problems connecting to my postgresql 7.2.1 running on my Debian
Linux box.

(as root)
$ psql template1 foobar
psql: FATAL 1:  IDENT authentication failed for user "foobar"

Could anybody tell me what the problem is?
The user "foobar" is created with the createuser command without any problem.

Here is the pg_hba.conf

local        all                                           ident sameuser
local        all                  trust