IMAP proxy advertising MAILBOX-REFERRALS and confusing Pine

[David Mayo]

We undertook the first stage of our IMAP server upgrade yesterday and 
introduced a front-end proxy running Cyrus 2.2 in front of our sole 
back-end server running Cyrus 2.2.

Since the upgrade, when a Pine user sends an email, the email is sent 
fine however when Pine appends the message to the sent-mail mailbox it 
asks the user to reauthenticate. Looking at the telemetry, the proxy 
server is advertising MAILBOX-REFERRALS[1] and Pine is trying to use 
them[2] but isn't able to silently reauthenticate the user.

Looking at the man pages for imapd.conf there is a useful feature 
proxyd_disable_mailbox_referrals however this was introduced in Cyrus 2.3.

Does anyone have any suggestions as to how to stop the front-end proxy 
server from advertising MAILBOX-REFERRALS and/or for Pine to ignore such 
capabilities.

Many thanks,


Dave.

David Mayo
Networks/Systems Administrator
University of Bath Computing Services, UK

[1]
* OK imaphost.bath.ac.uk Cyrus IMAP4 Murder v2.2.13 server ready
1 capability
* CAPABILITY IMAP4 IMAP4rev1 ACL QUOTA LITERAL+ MAILBOX-REFERRALS 
NAMESPACE UIDPLUS ID NO_ATOMIC_RENAME UNSELECT CHILDREN MULTIAPPEND 
BINARY SORT THREAD=ORDEREDSUBJECT THREAD=REFERENCES ANNOTATEMORE IDLE 
STARTTLS AUTH=GSSAPI SASL-IR
1 OK Completed

[2]
<1249984767<00000009 RLIST "" INBOX.sent-mail
 >1249984767>* LIST (\HasNoChildren) "." "INBOX.sent-mail"
00000009 OK Completed
<1249984767<0000000a APPEND INBOX.sent-mail {335}
 >1249984767>0000000a NO [REFERRAL 
imap://;AUTH=*@imap-backend1.bath.ac.uk/INBOX.sent-m
ail] Remote mailbox.