[Dovecot] Dovecot Authentication through different IMAP server?

[Robert Schetterer]

Am 25.09.2012 23:34, schrieb Marc Perkel:
> Just wondering - is there any way for a dovecot server to authenticate
> against a different IMAP server?
> 
> Here's what I'm thinking. I run a spam filtering service and thinking
> about a way to give users access to their stored spam on my servers.
> However real email is forwarded to their server, So I'm wondering if I
> can configure dovecot somehow to do a back end authentication to their
> email account to gain access to their spam.
> 
> Open to suggestions
> 

i am not sure your idea is the best way to goal
your target, running a i.e amavis filter gateway before postfix with
some style of quarantaine
seems to me a better idea

however

sasl can do auth against imap
i.e ( attention examples may be outdated or different by other distro
config style and/or dovecot versions)

MECH=”rimap”
FLAGS=”-O imap.server.name”

http://blog.travisz.com/2010/12/17/debian-mail-server-with-postfix-dovecot-and-saslauthd/

    #vim /etc/dovecot/dovecot.conf

Look for a line that starts with “auth default”.  Once you fine that
line, insert the following:

    auth default {
    mechanisms = plain login
    passdb pam {
    }
    userdb passwd {
    }
    socket listen {
    client {
    path = /var/spool/postfix/private/auth
    mode = 0660
    user = postfix
    group = postfix


there might better possibilities, wait until more response from the list

-- 
Best Regards
MfG Robert Schetterer