[Mailman-Users] Blacklisting Users in Newsletter

[John Griffin]

Hi this is a bit of a newbie question so sorry if it has been asked
before.
I'm evaluating various list managers to look after a newsletter mailing
list. The feature I'm specifically after, is the ability to allow users
to "unsubscribe" without actually having their account removed from the
system.

Basically I will get a list of names and email addresses dumped out of a
separate business application on a weekly basis. What I am trying to
achieve is the ability to import that list into the list manager,
without re-adding users who have previously unsubscribed from the
newsletter.

I notice that there is a "nomail" feature in the Mailman package. Can I
use this to accomplish what I am after? 
Seeing as users will not be allocated a username or password, I also
need to be able to achieve this without having them log onto a web page
to set this, so is it possible with an email based "nomail" command
rather like the "unsubscribe" command.

Is this possible?

TIA

John Griffin