As part of my user migration process perl script, user's messages are added to their Zimbra account using the following command:

system ("/opt/zimbra/bin/zmmailbox -z -m $user addmessage  /$dirname /tmp/$user/$dirname/mail_$dirname$count.txt");
where $user is the username of the user currently being processed, and /$dirname /tmp/$user/$dirname/mail_$dirname$count.txt is the path to the most recently processed message, stored as a .txt file.

Basically, I'm after a way to tell Zimbra to leave the 'Date' Field of the header of messages I am importing as it is, rather than changing it to the Date/Time of the import.

I've checked the value of the Date field during processing, and it remains the correct (original) value right the way through. It is only when I run the zmmailbox command that it is changed.

I have tried to do some research on this and am aware that there is a -d option for zmmailbox addmessage, as seen here

I would just like to avoid having to do extra converting during the migration process.