[OpenAFS] mail spool on AFS

[Craig_Everhart@transarc.com]

What we used at CMU for a million years was a solution that delivered
mail as separate files in the $home/Mailbox/ directory, with a directory
DB that allowed the mail deliverers to find $home pretty effectively. 
(This is before X.500, let alone LDAP.)  This let each user share their
quota for mail and other stuff, and it avoided the byte-range locking
stuff, using whole-file (AFS) file locking.  Mail readers had to know to
get a whole-file lock on each new message before incorporating it into
the user's pool of mail, but it was a small thing at the time.  This
does give you reasonable delivery fan-out; you can set up an additional
MX server that can assume some of the load without trying very hard.

		Craig