[Mimedefang] question

[Dan Tulovsky]

Hi.

We have one old domain that is a horrible SPAM target.  Roughly 5000-6000
emails come in a day for accounts that don't exist.  I am trying to shut it
down and am told there is only one user left.  Until he switches over, the
emails keep coming.

My question is.  Can I accept email for just this one user at thisdomain.com
and reject everything else?

Thank you much
Dan