The reading confirmation is put in the Outbox so that it will go out the next time that you send/receive mail.
The reading confirmation is addressed to the sender of the original mail (who requested a confirmation).

That's all good, isn't it?

You can configure reading confirmations in the Properties of that account. Go to Account | Properties | Templates | Reading Confirmation, and there you can make changes to the text (including macros) and to how it behaves (put in  outbox or send immediately, etc).

My own confirmation texts look like this:

Confirmation of receipt
-----------------------
Thank you for your message of %ODateEn %OTimeLongEn
to %OToName, regarding "%OSUBJ".
It will be attended to and/or answered as soon as time permits.

Regards,
MyCompanyName

-Daniel-

Footer with contact details
%Subject="Confirmation: %OSUBJ"
%FROM="MyCompanyName <info@MyCompanyName.com>"