pg_restore error - Mailing list pgsql-general

What does this error mean?

    pg_restore: [tar archiver] could not find header for file 1765.dat
in tar archive


All of a sudden, I'm encountering this error as I debug a problem
with the db interface I'm using.  My backups are created using a
script that hasn't changed recently, though I have just upgraded OS
from MacOSX v10.4.2. to 10.4.3.  My backup script executes:

    pg_dump -Ft -b -v source_name > output_name

Verbose output yields no error messages.

MacOSX v10.4.3
PostgreSQL v8.1.0
Psycopg2 v2.0b5


Any suggestions?

Thanks in advance!
Scott