> I'm more worried about whether openwebmail will work
> over dovecot without modification?
It will work just fine. I've been using and building servers with the Dovecot
stuff ever since it hit the testing repositories.
> Secondarily I utilise dnsbl's via sendmail.cf - I assume these will be lost
> entirely, does dovecot have a suitably easy system for using dnsbl's?
Once you switch to dovecot, you'll also get a new sendmail.cf installed. So
yes, your custom additions to sendmail.cf will be lost and have to be
re-added again manually. Do not simply copy the old sendmail.cf back,
otherwise you risk that some things will not work entirely right.
> Finally I use a custom /etc/procmailrc - will this be affected?
No. BlueQuartz by default doesn't provide /etc/procmailrc, so the update will
not affect it and that file will remain unmodified.
With best regards,