Emails without Date: header are always on top

[sebastianas]

Hi,

just noticed that I received a handful of emails without a Date: header. My imap based email client seems to look at the INTERNALDATE attribute (from IMAP) and has something sane. My imap-synced maildir preserves INTERNALDATE as "modify" date of the file. Would it work to use this in case the Date: Header is missing?

Sebastian