[Postfix-es] Disclaimer en el encabezado

[Juan Carlos Bravo Celis]

Hola a todos,

observando las cabeceras de algunos correos, he visto que muchos
tienen un X-Disclaimer,, alguien sabe como poner esta opcion en
postfix

por ejemplo este encabezado

Sender: webmasters en bbc.co.uk
X-Disclaimer: This message was sent to you using the "E-mail a
  friend" facility on http://www.bbc.co.uk/news/ The BBC is not
  responsible for the content of this e-mail, and anything said in
  this e-mail does not necessarily reflect the BBC's views.
X-HTTP-UserAgent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.2)
  Gecko/20061023 SUSE/2.0.0.2-1.1 Firefox/2.0.0.2
MIME-Version: 1.0
Content-type: text/plain; charset=iso-8859-1
Content-transfer-encoding: quoted-printable


Saludos

JCarlos