Mysqldump produces bad sql on 5.1.39 "OS X" PPC 64-bit

[René Fournier]

So... I'm trying to export a fairly large database (~10 GB). I've done it dozens of times
before, using scripts on a regular basis. Now, the database is growing, and lately, every
dump file produced has problems. When I try to run "mysql -u root -p < dump_file.sql",
MySQL will fail and return an error -- always different with each dump_file. A few recent
examples (of dump files produced on different days):

ERROR 1300 (HY000) at line 426: Invalid utf8 character string: '?03422'
ERROR 1136 (21S01) at line 6300: Column count doesn't match value count at row 6253
ERROR 1136 (21S01) at line 7493: Column count doesn't match value count at row 7645

When I examine the original database at the places that, in the dump file, there is a
problem, the master data is fine. So, what can I try? I've posted an earlier version of
this problem, and there were some good ideas, but none of them apply or have helped in my
case. I increased max_allowed_packet to 256MB. I've run mysqldump on the server itself, as
well as from a machine on the local network. I've exported across the network over TCP/IP
and over AFP. Nothing works -- I always get an error in the mysql dump file.

On the other hand, if run mysqldump on other, much smaller databases on the same server,
the dump file imports fine into other MySQL instances.

Ideas? Anyone, anyone? Bueller??

...Rene