[Exim] burst detector

Hi all,

I'm pretty sure this isn't possible, but just in case,

we have a computer on the network (a Macintosh) which every 4-6 months
decides that it wants to repeat e-mailing ... it sends thousands of copies
of the original e-mail per minute, is there any way to restrict the number
of e-mails sent per minute from a particular user, or, more importantly,
alert the systems admin team based on frequency?

Unfortunately we do have to support this system (it always seems to be
produced by the same user, but on one of a set of systems), and telling the
user to change over to PCs/ Jump off a bridge are not options.

Thanks for any help you can provide,

Zed