Requestor Correspondance in double with $ParseNewMessageForTicketCcs

Hi,

I’ve activated $ParseNewMessageForTicketCcs and generally everything is
working perfectly. There is however one case where individuals are
getting correcpondance in double.

Here is an example:

Someone opens a ticket in RT by sending a mail:From: joe@domain.tld
To: rt@domain.tld
Cc: joes_boss@domain.tld

joes_boss@domain.tld is added as a Watcher by RT. Ok so far.

Now suppose joe@domain.tld replies to a mail sent by RT and adds
joes_boss@domain.tld as a Cc: in the mail.

Then joes_boss@domain.tld gets a copy of the mail directly from
joe@domain.tld and another copy of the mail from RT.

It seems many users do not “trust” RT to notify the CCs and insist on
adding them again in every correspondance.

Is there any way to prevent this?