BUG #2360: Backup produces "ERROR: could not convert UTF8 character to ISO8859-1"

The following bug has been logged online:

Bug reference: 2360
Logged by: JP Glutting
Email address: jpglutting(at)oqua(dot)udl(dot)es
PostgreSQL version: 8.1 (8.0)
Operating system: Windows XP SP2
Description: Backup produces "ERROR: could not convert UTF8 character
to ISO8859-1"
Details:

There seems to be a bug in version 8.1 that produces this error when doing a
pg_dump (or pg_dumpall) of a database with certain characters in it. I am
not sure exactly which characters they are, but they did not cause a problem
in Postgres 8.0, because some of the databases that I cannot backup were
backed up from 8.0 and restored into 8.1 (there are also problems with data
entered directly into Postgres 8.1).

I have a test database with a single table in it as a test case. I can
backup this table (or database) from Postgres 8.0, and restore it into both
8.0 and 8.1. I can also back it up again from 8.0, but it will not backup
(or dump) from 8.1 (either from the command line or pgadmin3)

I can provide the test datbase (or table) in any format you would like. I
have yet to test this on Linux, but I will have a test box with Ubuntu 5.10
and Postgres 8.1 available soon.