Best Practices for rotating syslog logs on RHEL with different schedules?
Solution 1:
Set up a separate block for the messages log in /etc/logrotate.d/rsyslog (or whatever it's called on your install). It should use the setting for the specific log file match preferentially to a general one.
No, as Zoredache mentioned, multiple HUPs shouldn't break anything unless you're really hammering rsyslog anyway.