Backup and restore UTF8 data

Hi,

I am trying to backup an installation (8.0.3) and restore it to a new
(8.2.1) installation.  I am am running the following command the backup
the data.

pg_dumpall > outfile

Then on the new machine I am simply running:

ENCODING=UTF8 psql -f outfile postgres

I get the following error for some of the records.

psql:outfile:151275: ERROR:  invalid byte sequence for encoding "UTF8": 0x92

Does anybody know what I can do to fix this?

Benjamin