Apache has been segfaulting when restarted for weekly log turnover every Sunday morning since the major upgrade on the server a couple of weeks ago.
PS the major outage a couple of weeks ago was a hugely necessary OS upgrade from FreeBSD 5.3 (pretty much what I installed three and a half years ago when I built the server, bar a few security upgrades) to FreeBSD 7.0. This upgrade became necessary as I could no longer apply security fixes to applications because FreeBSD 5.x became unsupported a few weeks ago.
I'm still monitoring little glitches like this Apache problem and will be dealing with them as soon as they're diagnosed.
Sorry for any inconvenience.