Understanding the limitations of Dovecot Submission Service

[R. Diez]

Hi all:

The Dovecot Submission Service is very enticing for laz... I mean for busy people like me. A couple of lines in dovecot.conf , and you have a local 
SMTP server that does authentication. No SASL loops to jump through! Very cool people like me also appreciate cool new features like BURL.

But now I want to understand its limitations. Say I just bought e-mail domain 
x...@example.org . Say employee A has e-mail address a...@example.org .

It this employee turns evil, will he/she be able to send e-mails impersonating b...@example.org ? Or does the Dovecot Submission Service check that he 
only has permission to send as a...@example.org ?

My requirements are pretty modest. Basically e-mail should just be sent all right. But are there any other reasons why I should avoid the Dovecot 
Submission Server anyway? The documentation does not really say much.

Thanks in advance,
  rdiez