[Exim] Email disclaimer filters

Hi,

It has been deemed necessary by the legal bigwigs where I'm based to
start using outgoing email disclaimers for all of our mail. I'm aware
of the facilities within Exim to use transports to handle this sort of
thing, but what I'm not too sure about is writing a good filter to cover
all scenarios with relation to MIME attachments, etc.

Does anybody have any good pointers to working filter scripts, etc?
Regards,

    Martyn