[Lynne]

As already noted, it's a wait_timeout issue. I get the same on my server when I do backups because they are large and by the time the backup is finished and then the script wants to write to the cronlog table to say it did the task, the wait_timeout is over and done with and you get MySQL Server has Gone Away.

If you are getting that error because of other things on the site also, they I would worry about it. If it's just this daily backup script, I would remove the line in the script that logs the action and then the errors will stop.