[Mailman-Users] selective moderated list

[viswanathan]

hi all

I want to know whether the following is possible with mailman.

I run a mailserver for the domain xyz.com and i have created a list called 
everyone at xyz.com.

All the members who have an email id <at>xyz.com is a member of the list.

Now i want only a selected list of people to send messages to this list.
And for the remaining people it should bounce saying "you are not allowed to 
send mail to this id"

Please help me.

-viswanathan