fastforward handles qmail forwarding according to a cdb database.
It can create forwarding databases from a sendmail-style /etc/aliases
or from user-oriented virtual-domain tables.

fastforward supports external mailing lists, stored in a binary
format for fast access. It has a tool to convert sendmail-style
include files into binary lists.

fastforward is more reliable than sendmail. sendmail can't deal
with long aliases, or deeply nested aliases, or deeply nested include
files; fastforward has no limits other than memory. sendmail can
produce corrupted alias files if the system crashes; fastforward
is crashproof.

fastforward's database-building tools are much faster than sendmail's
newaliases. Even better, fastforward deliveries don't pause while
the database is being rebuilt.

fastforward does not support insecure sendmail-style program
deliveries from include files; you can use qmail's secure built-in
mechanisms instead. fastforward does support program deliveries
from /etc/aliases.
