[exim-dev] Extending quota warnings in the appendfile transp…

Hello,

I would like to implement some out of band mechanism for
quota warnings. Currently I can think of two ways:

quota_warn_recipient: Send the warning to a different address

quota_warn_authentication: Send the warning authenticated, and
use a user filter to act on mail from the authenticated address,
discarding the warning message afterwards.

Both would be private options for the appendfile transport.
Just ideas so far. Any opinions or better suggestions?

Michael