- one wants Exim to be able to create Maildir's 'on the fly' so long as
you have set up the new user with a password and identity..
THEN
- one must insure that whatever UID:GID Exim is executing that
particular operation as..
- Has the correct permissions *to cd / chdir into all the level(s)
*above* wherever the Maildir is to be created.. not just into the
'operating' level where it will do the mkdir from....
ELSE
- Which, while *N*X "conventional wisdom" can be confusing as the error
messages in /var/log/exim/main.log (in my case), will be a bit obtuse,
as they don't necessarily show the same path you expect, nor even one
that exist..
...to wit, in this case it said: "unable to chdir to /home/{$local_part}",
(which is not called for in ../configure, and does not exist)...
..when I expected "/home", "/home/mail", or "/home/mail/{$local_part}"
