Although previous posts explicitely stated that no non-ascii chars where
involved, I'm quite sure that this is in fact the problem. I created a
user with a non-ascii password, and immediately was able to reproduce
the problem.
Passwords entered in pgAdmin are in Unicode, and are converted when sent
to the backend. Unfortunately, at connect time some default conversion
rules are applied, so pgAdmin can't be sure whether converted or
non-converted passwords are needed; it will try both when connecting
interactively.
When libpq evaluates pgpass.conf (or ~.pgpass on *ix), it will *not* try
several conversions, instead it will use the string as-is.
I changed pgAdmin now to store the pgpass info in the format that it has
found suitable from the last successful connect. Please check the latest
snapshot (win32 available now, *ix tomorrow after nightly build), and
give me feedback if it works for you. If it does not, I really need the
pgpass.conf line to dig further.
Regards,
Andreas