[Mailman-Users] Mailman options

[lists at southernohio.net]

I have a customer that is essentially asking me for a mailing list that 
is not the traditional mailman way of doing things.  I started out 
customizing Mailman in several ways according to their requests, 
however they are, I think, needing another system and I'm just not sure 
where to find such a creature.

They had a problem where their provider started spamming their list and 
had to change, thus this is where I come into the mix, and they simply 
want to send out their own newsletters intermittently and not allow 
members to chat with each other, but when they send messages that they 
go back to the administrator.  They also do not want users to have to 
worry about passwords and they want unsubscription will be as simple as 
clicking a link in the newsletter.

One final kicker is that they want reporting on if members addresses 
have become invalid (ie messages bounced to them).

Can mailman be customized to function after this manner (basically 
providing a super clean interface for subscribers with the above 
options) or should I be looking for another solution?  If I should be 
looking for another solution does anyone know of such an application?

Thanks much for any help!

-George