* Added [security]/chroot option to config file, which causes Amavis
  to chroot() to the specified directory.

  + Preload many modules so we can run in chroot() without needing to
    go find them.

* Better error checking in various places.

* Unified error handling in some virus scanners and extractors.

* Turn some virus scanners and extractors into full-fledged objects

* Be pickier about MIME.

* Support for banning attachments by name
  ([filtering]/ban_attachment_extensions)

* Fix SMTP stuff so we don't accidentally lose messages if our relay
  server isn't available.

* Claim to support 8BITMIME and PIPELINING (do we?)

* Randomly changed some warning and error messages

* Add support for compress

* Don't require /etc/passwd to be available to change to a numeric UID
  (since it isn't if we're chroot).  Similarly, don't require
  /etc/group to switch to a numeric GID.