UserDB a.k.a. Sender rewriting implemented

[Matti Aarnio <mea@nic.funet.fi>]

  After several users asked for it, and I had personal needs for it,
  I spent couple evenings at the issue earlier this week, and now
  there is Sendmail 8 -like  UserDB  facility, although it is sort
  of "on all the time".

#
#  UserDB per sendmail's approach
#
#  This can be used to map local names into outgoing fqdn addresses.
#  There are white-space separated key and data fields.
#
#  Sendmail implements things called: ":maildrop" which is alike
#  standard aliases. (Except works at header rewriting also?)
#  Sendmail implements also ":mailname" things which map VISIBLE HEADER
#  addresses to other.
#
#     root:maildrop    sysadmin@here.dom,bill@three.dom
#     user:mailname  ->  user.name@here.dom
#     user.name:maildrop -> user
#
#  Sendmail has also mapping key  ":default:mailname"  however ZMailer
#  doesn't support that one.
#
#  CURRENTLY ZMAILER SUPPORTS ONLY "****:mailname" MAPPINGS
#  (2000-March-28)  Use standard aliases for maildrop mapping.
#
#  As the sendmail method is somewhat limited, the userdb mapping as
#  present at   crossbar.cf / internet()  function implements:
#     user:mailname                     ->  user.name@here.dom
#     user@some.dom:mailname            ->  user.name@other1.dom
#     <anylocalpart>@some.dom:mailname  ->  <anylocalpart>@other2.dom
#  mapping for allowing masking single users..
#

#user:mailname		user.name@here.dom
#user@some.dom:mailname	user.name@other1.dom
#@some.dom:mailname	@other2.dom


-- 
/Matti Aarnio	<mea@nic.funet.fi>