[Dovecot] migration to maildir and arrival time

Hello.

I am currently testing dovecot (0.99.10.8, Debian woody from backports), with the maildir storage.

I have noticed that when I use the mailutil tool from uw-imap distribution to transfer my IMAP mailboxes from our current server (uw-imap, mbx format) to the dovecot one, the mails arrival time are apparently lost. I can see this in Pine, using the Arrival sort: the mailboxes on the originating server and dovecot server are not ordered the same. If I use the mb2md perl script to transfer the same mailbox, I see the same behaviour.

Is this normal ?

Thanks.

-- Nicolas