Fwd: resetting superuser password - Mailing list pgsql-admin

I have lost the superuser (user postgres) password, but I still have the unix root password.  Is there anything I can
doto reset the postgres user's password (short of reinstalling Postgres)? 

Obviously, I can su to unix user postgres, but this does not seem to advance my cause, as doing "psql -U postgres"
stillprompts me for a password, which is not the same as the unix postgres user's password.  

OS: RedHat 9

Help!

Thanks,
Marc