Hi Franz-Josef,
I assume, that the server-side max_allowed_packet size is too small. See the following example:
shell> mysql -uroot --max_allowed_packet=128M
mysql> show session variables like '%packet%';
+--------------------+---------+
| Variable_name | Value |
+--------------------+---------+
| max_allowed_packet | 1048576 |
+--------------------+---------+
shell> show global variables like '%packet%';
+--------------------+---------+
| Variable_name | Value |
+--------------------+---------+
| max_allowed_packet | 1048576 |
+--------------------+---------+
See also this:
"When you change the message buffer size by changing the value of the max_allowed_packet variable, you should also change the buffer size on the client side if your client program permits it. On the client side, max_allowed_packet has a default of 1GB. Some programs such as mysql and mysqldump enable you to change the client-side value by setting max_allowed_packet on the command line or in an option file."
http://dev.mysql.com/doc/refman/5.1/en/server-system-variables.html#sysvar_max_allowed_packet
For you I assume, it is just the other way around.
If it is not. Then try to make the value on both sides just a bit bigger. I think there were some bugs in older releases...
One fundamental thing you missed is doing regular test restores. Otherwise you would have found this already earlier.
Best regards,
Oli
--
www.fromdual.com