> an error has occured:
>
> Error connecting to the server: FATAL: IDENT authentication
> occured for user "myusername"
That's because PSQL by default uses a unix socket and your previous
email showed you were using a network socket for PGADMIN. Which is
fine, except that the latter has to use the IDENT network service
to figure out who you are. If PSQL is working and PGADMIN is not,
I would suspect that you don't have a working identd running yet.
Either install one, eg
apt-get install pidentd
or tell pgadmin3 to use a unix socket (see list archives under my name).
If you're running Debian Stable, you need to use custom built .deb files.