[Usagi]

Ok, here's the thing. I'm writing an IMAP server. Why, you may ask. Well, it's part of a larger project and none of the existing ones fit the bill, so I am writing my own.

That side of things isn't a problem - I am an experienced programmer with lots of experience in client-server programming.

The problem is that the IMAP server I have written doesn't work with Thunderbird. It works fine with Windows Live! Mail, and with Outlook and Outlook Express.

The problem is thus:

Thunderbird connects to the server OK.
It gets the list of mailboxes OK.
It selects a mailbox OK.
It then just disconnects.

At this point on other servers it should be sending a UID request to get the contents of the mailbox, but it doesn't with my server and I can't work out why. Traces follow.

My server:

28942: >> * OK [CAPABILITY IMAP4rev1 UIDPLUS QUOTA CHILDREN STARTTLS IDLE]
28942: << 1 STARTTLS
28942: >> 1 OK Start TLS Negotiation Now
28942: << 2 capability
28942: >> * CAPABILITY IMAP4rev1 UIDPLUS QUOTA CHILDREN STARTTLS IDLE
28942: >> 2 OK CAPABILITY Completed
28942: << 3 login "xxxxxx" "xxxxxx"
28942: >> 3 OK LOGIN Ok
28942: << 4 select "Sales"
28942: >> * FLAGS (\Draft \Answered \Flagged \Deleted \Seen \Recent)
28942: >> * OK [PERMANENTFLAGS (\* \Draft \Answered \Flagged \Deleted \Seen)] Limited
28942: >> * 311 EXISTS
28942: >> * 311 RECENT
28942: >> * 8 UNSEEN
28942: >> * OK [UIDVALIDITY 1] UIDs valid
28942: >> * OK [UNSEEN 241] Message 241 is first unseen
28942: >> 4 OK [READ-WRITE] Ok
28942: << 5 logout
28942: >> 5 OK LOGOUT Completed

Trace from Courier IMAP:

>> * OK [CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA IDLE ACL ACL2=UNION STARTTLS] Courier-IMAP ready. Copyright 1998-2010 Double Precision, Inc.  See COPYING for distribution information.
<< 1 login "xxxxxx" "xxxxxx"
>> 1 OK LOGIN Ok.
<< 2 select "INBOX.test"
>> * FLAGS (\Draft \Answered \Flagged \Deleted \Seen \Recent)
>> * OK [PERMANENTFLAGS (\* \Draft \Answered \Flagged \Deleted \Seen)] Limited
>> * 4 EXISTS
>> * 0 RECENT
>> * OK [UIDVALIDITY 1272828277] Ok
>> * OK [MYRIGHTS "acdilrsw"] ACL
>> 2 OK [READ-WRITE] Ok
<< 3 getquotaroot "INBOX.test"
>> * QUOTAROOT "INBOX.test" "ROOT"
>> * QUOTA "ROOT"
>> 3 OK GETQUOTAROOT Ok.
<< 4 UID fetch 1:* (FLAGS)
>> * 1 FETCH (UID 1 FLAGS (\Seen))
>> * 2 FETCH (UID 2 FLAGS (\Seen))
>> * 3 FETCH (UID 3 FLAGS (\Seen))
>> * 4 FETCH (UID 4 FLAGS (\Seen))
>> 4 OK FETCH completed.
<< 5 IDLE
>> + entering idle mode
<< DONE
>> 5 OK IDLE completed

The only obvious difference is that courier supports Quota and my server doesn't. Also, I disabled TLS on the courier connection so I could get the trace.

It's really doing my head in. As I say it all works fine on other email clients, but Thunderbird is the one I need to support most. Another thing that's really annoying is that it was working ok at a much earlier stage of the development process (but the others weren't) and I can't work out what has changed.

Any thoughts or ideas would be greatfully received.