Regaining superuser access

I have a user with a problem on his PostgreSQL 8.1 server running
Windows:

The server only has one superuser, and for some reason he decided to
remove the logon privilege on this user in PgAdmin III. So now he has
lost superuser access to the database server.

Is there some way to override this setting? Or some way to trick
PostgreSQL into creating a new superuser without superuser access?

I can log on to the database with other users, but even if I add
"trust" to pg_hba.conf PostgreSQL will not let me access the database
as the superuser.

I have remote access to the server, which is now on a ship outside of
Madagascar.

The problem we have seems to be the same as this user reports (but got
no reply):
http://www.nabble.com/Fatal-error%3A-role-%22postgres%22-no-login%21-tp14537100p14541715.html

I have looked in the documentation, but don't seem to be able to find
any solutions. Pointers are welcome!

Kind regards,
Bernt