Again, problem with pgbouncer

Hi,

- PG 9.0.10
- Pgbouncer version 1.4.2

Not long ago, during the last server reboot for us, we had fixed the
really painful (and largely mysterious) process of setting up
pgbouncer.

File permissions and other mysteries were solved with help from Raghavendra:
http://permalink.gmane.org/gmane.comp.db.postgresql.pgbouncer.general/854

After a long we rebooted our server today and again, as if on cue,
pgbouncer has problems yet again :(

PG itself is running without problems.

The Pgbouncer process starts properly too. All the auth file, log file
etc are setup as mentioned in that URL above. We haven't changed
anything at all!

At first, just connecting via pgbouncer port was giving the "no user"
error. Which is funny, because the authfile has been working without
problems forever. The .pgpass file had the same problems, and is still
the same all this time.

So, upon reading that old thread again, I guessed that the "postgres"
user permissions were needed, so I did this:

chown -R postgres:postgres /etc/pgbouncer
chown -R postgres:postgres /var/run/pgbouncer/
chown postgres:postgres /var/log/pgbouncer.log
chown postgres:postgres /var/lib/pgsql/pgbouncer.txt

Then restarted both PG and Pgbouncer.

Now pgbouncer won't do anything at all. Trying to connect to psql via
the pgbouncer port gives this error:

psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/tmp/.s.PGSQL.6789"?

And in the log is this line:

2012-10-01 06:12:00.703 3754 FATAL @src/main.c:553 in function
write_pidfile(): /var/run/pgbouncer/pgbouncer.pid: Permission denied
[13]

What now? Would appreciate some pointers.

Thanks.