Message-problems?

I've got a lot of reports about that the server sends the error-messsage:

Error: mysql->big_query(): Query "select max(nr) from messages where `from`=4836" failed (Lost connection to MySQL server during query)

when sending messages. It works for me though, and I have no idea why it's not working.

I deleted a lot of error-reports about this in the Elftown, bugs forum, after reading them. They are appreciated, but there is no need to save a lot of copies of the reports.

Update: It must have been a lack of memory-problem. Probably the Elftown-server took up all the memory so that the database didn't work. Now the Elftown-server is restarted, and much smaller again.