pg_dump not working

Howdy,

I've come back from a two week holiday to find that pg_dump isn't working.
I'm running Postgresql 7.0.2 on FreeBSD 2.2.8.
I've stopped the postmaster, backed up the database directory using tar for
safety, and performed a successful vacuum analyze.
The error I'm getting is:

PQgetvalue: ERROR! tuple number 0 is out of range 0..-1
Segmentation fault (core dumped)

Any ideas?

Regards,
Chris Knight
Systems Administrator
AIMS Independent Computer Professionals
Tel: +61 3 6334 6664  Fax: +61 3 6331 7032  Mob: +61 419 528 795
Web: http://www.aims.com.au