'Unknown command' from loading mysqldump file

If so happen when you load a mysqldump file get these errors,

mysql < mysqldump_021010.sql
ERROR at line 5122: Unknown command 'ufffd'

You need to increase max_allowed_packet and try again.
The error itself is not very informative, actually somewhat misleading.
It's probably because you have big insert statement in your dumpfile the exceeded the limit and mysql interpret row data after that as command.

In my case, running mysql --max_allowed_packet=64M fixed the issue. The default is 16M in mysql 5.0 and 5.1

Actually according to MySQL doc, it is safe to increase the value of this variable because the extra memory is allocated only when needed. So 1G here we go.