[Alug] Log files (/var/log/messages)

Folks, I just logged onto our firewall box for my periodic peruse, and I noticed that the /var/log/messages file, created on 28 Jun is 0 bytes long. All the permissions, ownership and so on seem to be ok, and it certainly used to log stuff. Any ideas as to why it should stop logging? I'm a bit concerned about this... -rw-r----- 1 root root 0 Jun 28 00:00 messages Also, how do I force an archive and compression of a log file? Cheers, Laurie.