[Dovecot] Thunderbird 1.5 and messages with no Date: header

hi,

some of my Thunderbird users have a minor but annoying problem with messages that have no Date: header.

these clients use BODY[HEADER.FIELDS (Date)] as the date for messages. when a message has no Date: header, they display the date as 01/01/1970 10:00:00 because Dovecot returns empty string.

would it be possible for Dovecot to return INTERNALDATE instead, for messages that contain no Date: header? I know this is not *technically* correct, but it's a reasonable best-guess, and better than returning nothing. perhaps as a client-workaround?

I vaguely recalled a previous message about this, but I couldn't find it today.

grant.