Replying to E-mails I did not receive

Hi! I tested a few patches sent to lists I'm not subscribed to. I want to reply to the thread with my "Tested-by: " and "Acked-by:", but I'm not sure what is the best way to do it. Is it enough to simply compose a new message with the original text as a reply to the correct message id? How you usually do that? Thank you! Peter -- Peter