Errors with pg_dump

I would like to move some data from an older installation of PostgreSQL to
a newer.  When doing 
"pg_dump persondb > db.out" I get the following error message:

"dumpSequence(person_sek): 0 (!=1) tuples returned by SELECT"

The "person_sek" is a sequence in the database.

The version of PostgreSQL in question is 6.3.2, running on RedHat Linux
5.1/5.2.  The actual database (persondb) seems to be running fine in all
other respects.  It can be queried with psql, and is used as the backend
for a set of web pages.

Help, anybody?

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