Hi Reuven,
well, this is a real neat feature that a lot of people would like to see, and probably not just for forums but as a general service.
I remember that in ACES (ACS 4.x) they tried to do something like that for forums, but not sure right now, maybe Caroline know about it. AFAIK there is no implementation of this yet for oacs.
Basicly, just come to my mind, you'll need a parser for handling diffent email formats (there's one good Oscar said) for all the incoming emails, and embeded ID for obvious reasons, including checking "email from" for security issues. There is no de facto MTA for oacs, or is one? I also use qmail.
