Submitting spam mail for training SA

[Nikolaos Milas]

Hello,

We have a Postfix 2.9.4 with Amavisd-new 2.8.0/ClamAV/Spamassassin on 
Centos 6.3 (x86_64) used as an incoming mail filtering gateway which 
relays clean (only) mail to an internal final destination mail server 
(Postfix/Dovecot).

We are not using Maia or other such systems supporting per user 
filtering/spam rule settings. (We want to keep the setup as simple as 
possible and controllable by the admins.)

I would like to setup a spam mailbox (like: spam at example.com) where 
users can submit what they deem as spam, and which can be used to train 
SpamAssassin. The idea is to receive reported spam as attachment (one 
per mail), so we can process it later, e.g. by saving spam mail files in 
a directory and running:

    sa-learn --spam /path/to/spam/folder

Questions:

  * Do regular eml files (of spam mail messages) qualify for such use
    (i.e. does sa-learn understand them properly)?
  * What happens with spam messages forwarded from Outlook clients which
    will forward as msg and not as eml? Do we need a msg-to-eml
    converter script to process these files?

Has anyone here set up something like that and could suggest/provide a 
script or similar, which would accomplish this task (I don't want to 
re-discover the wheel)?

Any advice will be appreciated.

Thanks in advance,
Nick