Well, from the description of Chalmers' mail setup, it seems quite
possible that it could lose mail. The semantics of flock in AFS
pretty much dictate that you have to get a flock on a separate file
than the one you are trying to mediate access to.
Also, as there seems to be a program that authenticates itself as
"postman", it seems that a sufficiently motivated person could examine
the program in order to authenticate themselves as "postman" and be
able to read everyone's mail.
AMDS has had a lot of work put into it in order to get the AFS
semantics right. There's a fairly high confidence that mail will not
be lost. I personally don't have much confidence in other, more
ad-hoc schemes.
_.John
