You have just installed /usr/local/bin/qmail-auditor
which can be enabled by wrapping qmail-queue and naming the original qmail-queue
as qmail-queue-real, for example:

 mv /var/qmail/bin/qmail-queue /var/qmail/bin/qmail-queue-real-auditor
 ln -s /usr/local/bin/qmail-auditor /var/qmail/bin/qmail-queue

Now you can configure qmail-auditor, its control file is

	/var/qmail/control/auditor

This file's format must be in the form:

  <field header>  <regular expression>            <e-mail to forward>

Where
  <field header>	= from|to|all
  <regular expression>	= sender or recipient e-mail address (according
			  to <field header>), re_format(7) compatible
  <e-mail to forward>	= whom qmail-auditor will copy audited messages to

You can have multiple rules (one per line). Working example of control file:

from	*@some.domain.br	auditing@mycompany.com
to	user@some.domain.br	auditing@mycompany.com
all	sales@domain.br		salesauditing@mycompany.com

The README file was installed on /usr/local/share/doc/qmail-auditor