Implement RRS - a backdoor for non-SRS forwarders.  User lists non-SRS 
forwarder accounts, and a util provides a special local alias for the
user to give to the forwarder.  Alias only works for mail from that
forwarder.  Milter gets forwarder domain from alias and uses it to
SPF check forwarder.

adapt init script to work on RH9
Skip dspam when SPF pass?
Report 551 with rcpt on SPF fail?

Another special dspam user, 'honeypot', can be listed in innoculations.
All email to those addresses is treated as known spam.

Framework for modular Python milter components within a single VM.
Python milters can be already be composed through sendmail by running each in
a separate process.  However, a significant amount of memory is wasted
for each additional Python VM, and communication between milters
is cumbersome (e.g., adding mail headers, writing external files).

Backup copies for outgoing/incoming mail.

Allow multiple wiretap groups, each with its own destination.  Perhaps 
also copy incoming wiretap mail, even though sendmail alias works perfectly
for the purpose, to avoid having to change two configs for a wiretap.

Provide a way to reload milter.cfg without stopping/restarting milter.

Allow selected Windows extensions for specific domains via milter.cfg

Fix setup.py so that _FFR_QUARANTINE is automatically defined when
available in libmilter.

Keep separate ismodified flag for headers and body.  This is important
when rejecting outgoing mail with viruses removed (so as not to
embarrass yourself), and also removing Received headers with hidepath.

Wrap smfi_setbacklog(int) - but it is only available in sendmail >= 8.12.3,
  so how can we detect whether to wrap it?

Need a test module to feed sample messages to a milter though a live 
sendmail and SMTP.  The mockup currently used is probably not very accurate,
and doesn't test the threading code.