On Wed, 20 Feb 2002, Michael Weinberger wrote:

> Darrell May <[EMAIL PROTECTED]> schrieb:
>
> > 1) Please explain in detail the problems you have experienced with
> > UW-IMAP.
>
> a) The unmodified UW-IMAP (with mbox format) works great. The UW-IMAP in SME
> is patched for maildir support. This patch uses the unix time stamp of every
> message as the UID. When the message is moved to another folder the UID must
> change and therefore the time stamp must change. As a result the message's
> arrival date has changed.

The last statement is only true if the arrival date is derived from the
file time stamp. AFAICT, there is no concept of "arrival date" in the
IMAP protocol, although there is mention of it in a draft sort extension
of the IMAP protocol:

http://www.ietf.org/internet-drafts/draft-ietf-imapext-sort-08.txt

Here, the "arrival date" is not clearly defined, it is just the "Internal
date and time of the message".

Using the sort extension doesn't pass the IMAP server's internal notion of
the "arrival date" down to the client, it only defines the order of
presentation of messages.

Now the maildir format does encode the UID in the timestamp of the message
file, but the arrival time (if defined as the time when the message is
added to a maildir, which might be when the message is moved from folder
to folder), is encoded in the filename of the message file, so the IMAP
daemon is capable of sorting using filename to determine arrival order,
iirespective of timestamp. I haven't looked through the code, so I don't
know what it does.

> Some clients display the sent date from the "Date:" line (like IMP)
> but the sort order is wrong, since UW-IMAP still sorts by arrival
> date. You can easly verify this in IMP.

Can you define what "sort order is wrong" means? The IMAP sort extension
includes both sort-by-arrival and sort-by-date. The sort order should
therefore depend on what the client requests.

> b) With Outlook or OE you will get the error as described in my initial
> posting and in previous postings on this list. Addionally Outlook does not
> show messages newer than the file .uidvalidity (which is generated by
> UW-IMAP in every mailbox) . When you delete the .uidvalidity file, as
> recommended in previous postings, Outlook can retrieve all messages, but
> then all messages are shown with the date of newly created .uidvalidity
> file.

That definitely sounds like a problem with Outlook. The .uidvalidity file
is only used to preserve a UIDVALIDTY number. If a client receives a
larger UIDVALIDITY number that it has cached, it should discard its own
cache of UIDs, and refresh that information from the server. It shouldn't
be used for anything else.

That's not to say that the different UIDVALIDITY implementation which
Courier has doesn't happen to work with Outlook.

> > 2) Would it not be possible to fix these issues and remain with UW-IMAP?
>
> Dont think so. IMO, the problems are inherent in the design of the maildir
> patch.

I don't think that we can safely conclude that without knowing exactly
what should be different in the IMAP protocol implementation for Outlook
to be happy.

That's not to say that switching to Courier wouldn't be a good idea.

--
Charlie Brady                         [EMAIL PROTECTED]
Lead Product Developer
Network Server Solutions Group        http://www.e-smith.com/
Mitel Networks Corporation            http://www.mitel.com/
Phone: +1 (613) 368 4376 or 564 8000  Fax: +1 (613) 564 7739



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