unable to restore 8.2.5

Hello.

I am having some trouble restoring a dump from the production system
over to a test system. Both servers are 8.2.5 and both use UTF-8. The
vrc_error table have ~36 mill rows on the production system, but none
of those are restored to the test system.

pg_restore: [archiver (db)] Error from TOC entry 1665; 0 333256 TABLE
DATA vrc_error primar
pg_restore: [archiver (db)] COPY failed: ERROR: invalid byte sequence
for encoding "UTF8": 0x81
HINT: This error can also happen if the byte sequence does not match
the encoding expected by the server, which is controlled by
"client_encoding".
CONTEXT: COPY vrc_error, line 34500528

Looks like I have managed to insert an illegal character into the main
system that does not conform to UTF-8. Anything I can and should do to
work around this issue?

Btw, we also use wal shipping and warm standby for the main database
and that works perfect.

Regards,
- Tore.