Thanks for replying my postings. We need to post this issue since there're
circumstances where duplicate messages (with the same message-ids) occur:
Some users own email aliases in other servers which are forwarded to their real
email addresses in our server. Now, a lot of senders for some reasons put the
recipeints' email aliases in To: field and the real email address in Cc: field;
so the receipients receive two same messages in our server. Our users currently
want that mhonarc translate every mail in their folders regardless of same
messages, so if they receive 10 messages, say that 2 of them are the same, they
also want to have 10 mhonarc generated htmls, so that they will know that they
actually receive duplicate messages and if they want, they can delete them by
themselves (with pine or whatever).
