Emailer 1.1 incorrectly reports messages sent in 1999 using a four digit year in the header as being sent in 1919. Messages with a two digit year do not have this problem.
You can change the sort order by unchecking the option to "use sender's date/time for received mail." This will sort the messages by the received date instead of the what Emailer thinks is the sent date.
The issue does not effect Emailer 2.0.x.