Hello, there is a way with a sieve rule to add a Date: header when it is missing? Adding one with the time of reception of the message or using the date from the the first Received: header would be good options.
Unfortunately I'm receiving some useful automated messages that lack a Date header and this screws up the sorting in my imap clients. I have a script to fix those acting on the Maildir storage, but I would prefer to have the thing solved more radically. Thanks. Cheers, Daniele