I got up "Zimbra 7.2.1 server" on fedora 13 from a backup.
From there the logs do not work:
/var/log/maillog is empty.
/opt/zimbra/log/mailbox.log is empty
Statistics show no data available

that I can do to make the logs work?

[zimbra@mail ~]$ zmloggerctl restart
Stopping logswatch...done.
Starting logswatch...done.
[zimbra@mail ~]$ zmloggerctl status
[zimbra@mail ~]$ ps ax | grep zmlogger
21825 ? S 0:00 /usr/bin/perl /opt/zimbra/libexec/zmlogger
21872 ? S 0:00 zmlogger: zmrrdfetch: server
21953 pts/2 S+ 0:00 grep zmlogger
[zimbra@mail ~]$