Toby, is this what you had in mind with that warning statement:
Warning: on any server that uses SMTP, it is a mistake to use multiple
retry rules distinguished only by "senders=" qualifiers. Internally, the
retry attempts are being tracked by the host only (which do not depend
on the recipient). Once a retry rule has been matched, and results in a
host error, its contents are used to set a retry time for the host, and
this will apply to all messages that would get delivered to this host, not
just those with specific senders.
To state it another way (but doesn't seem quite as easy to follow):
After matching a retry rule based on a "sender=" qualifier that results
in a host error, any subsequent emails with a different "sender="
qualifier and different retry parameters will not reset the previous
retry parameters for that host.
> We have a fair amount of exim expertise here, but nobody had come across
> this before.
I had not ever seen that before either. My system configuration is
relatively simple.
