Accessing to mail as another user

[Angel L. Mateo]

Hello,

	I'm looking for a way to access to a POP/IMAP account as another user 
different than me, but using my password. That is, I'm 
"someone at domain.com" and I want to access to "anotherone at domain.com" 
mailbox using the password of "someone at domain.com", not the 
"anotherone at domain.com" (something similar to master passwords, but 
without sharing any password). Obviously, in my LDAP backend I can 
configure something to authorize "someone" to access to "anotherone"'s 
mailbox.

	At this momment, I'm trying to use 
someone at domain.com@anotherone at domain.com as username, with a passdb that 
uses %{username}@%{domain_first} to authenticate the user, but I'm 
having problem to configure a userdb map to get the mailbox, because the 
%{domain_first} variable returns just "domain.com". To fix this, I could 
use "someone at anotherone@domain.com", but this has problems with virtual 
domains an different users with same username (someone at domain.com and 
someone at otherdomain.com).

	Looking at documentation, at [1], in the "auth_user" variable says: 
"... If username changes during authentication, this value contains the 
original username..." what leads me to think that there is some way to 
change the user during the authentication process, but I don't know how 
or maybe I'm assuming wrong.

	Any help with this? Thank you

[1] http://wiki.dovecot.org/Variables
-- 
Angel L. Mateo Martínez
Sección de Telemática
Área de Tecnologías de la Información
y las Comunicaciones Aplicadas (ATICA)
http://www.um.es/atica
Tfo: 868887590
Fax: 868888337