How do I configure Exim as part of TPC (http://www.tpc.int)?

How do I configure Exim so that it sends mail to the outside world only from a restricted list of our local users?

A site for which I provide secondary MX is down for some time. Is there a way to run the queue for that destination separately from the main queue?

We want to be able to temporarily lock out a user by disabling the password and moving the home directory to another place. How can we arrange to reject mail for users in this state?

How can I configure Exim so that all mails addressed to something@username.domain.net get delivered to /var/spool/mail/username?

How do I get exim not to add a Sender: header to locally originated mail?

Is there any way to have messages sent to a specific local address delayed by - say - 24 hours?

I have a mailing list exploder on one host, and three other hosts where I want to do the actual deliveries from. How can I get Exim to split a message into groups of recipients between the three hosts?

Can I configure Exim so that my gateway host sends a copy of each incoming message to each of two internal hosts?

How can I implement “SMTP-after-POP” with Exim?

I would like to “tap off” a proportion of real mail traffic from my live mail server to use in tests of a new server. I want to preserve the envelope contents, but to suppress any error notifications to the original sender.

How can I lookup data from a single file using both single IP addresses and IP address blocks as keys? I want to set smtp_accept_max_per_host by this means, and also include a default.