Automatically making Cc's ->BCc's on ticket creation

I have setup RT 2.0.15 to automatically parse new messages to add CC’s
to the CC list for the ticket’s life by modifying the
/path-to-rt/etc/ file:
$ParseNewMessageForTicketCcs = “true”;

This is working great except for one thing. When people reply-all to
the email they receive, the Cc’s get 2 copies (one direct from their
mail and one sent by RT).

I would like them only to get one copy total.

So I’m asking for advice to either:

  1. if the reply to a ticket already includes a CC listed, don’t have RT
    also CC the same email.

  2. Add Cc’s as BCc’s for the life of the ticket. (Similar to my
    admin-cc watchers who get email, but aren’t listed as a CC on the email
    that goes out).

Any ideas