disable confirmation email

Hi, I am posting emails top a blog and have added the the email address that is configured to receive the emails to be posted to a mailing list.
Not a good idea, as post now sends regular post confirmation emails as reply to the mailing list which will be distributed to all members of the list including post, which results in another email….

So I have set the interval to check for new emails to daily and hope to find a solution now.

I have not found an option to disable the confirmation email, can you give me a hint on how to disable it?
Thanks a lot!
cheeers, Dietmar