Software for employe-like tracking, particular with Email.app?

My pal Dave has a number of full and part time employees (all Mac) in sales-like roles. In short he wanted a > plugin, or even a separate app that just reads the MBOX file? > > To get an idea of > > a) What days emails were sent, (ie days they were working) > > b) Times that each email was sent, to see start/stop times. Essentially, it seems basically "a report on when emails were sent". (I guess, using Mail.app.) Can anyone think of something like this? Or perhaps, at least generally some Mac-focussed employee time tracking (or spying!) thing. You can imagine it would be quite useful for customer support stuff, you could get reports like... > Employee 13. 48 emails sent. 1015-1845 hrs .. etc. Any ideas?