Bug 355938

On a mailbox I have some mails which I am unable to mark as read, they are *always* marked as unread again. Even movin the mails to another folder makes them reappear in the original folder (unread again). Also, after moving, the copied emails are impossible to delete.

Reproducible: Always

Steps to Reproduce:
1. mark all mails as read in folder
2. switch to other folder and back to inbox

Actual Results:  
mails are maked as unread again

Expected Results:  
mails stay marked as read

From the log:

When marking as read:
log_koalarmclient: Check: "Do. Nov. 26 13:31:08 2015"  - "Do. Nov. 26 13:32:07 2015"
log_akonadi_mime: Mark all as:  "R"
log_imapresource: "INBOX"
log_kimap: "46,50,52,53,55 +FLAGS (\Seen)"
log_kmail: A Resource started to synchronize, starting a mail check.
log_kmail: Last resource finished syncing, mail check done
log_koalarmclient: Check: "Do. Nov. 26 13:32:08 2015"  - "Do. Nov. 26 13:33:07 2015"
log_kmail: A Resource started to synchronize, starting a mail check.


After switching back to the folder:

log_imapresource: ".INBOX"
log_kmail: Last resource finished syncing, mail check done
log_messagelist: Using model: Akonadi::EntityTreeModel
log_imapresource: Starting retrieval for  "INBOX"
log_kmail: A Resource started to synchronize, starting a mail check.
log_imapresource: Server bug: Your IMAP Server delivered an invalid UIDNEXT value. This is a known problem with Courier IMAP.
log_imapresource: Starting message retrieval. Elapsed(ms):  16
log_imapresource: MessageCount:  57 Local message count:  57
log_imapresource: UidNext:  0 Local UidNext:  0
log_imapresource: HighestModSeq:  0 Local HighestModSeq:  0
log_imapresource: Invalid UIDNEXT
log_imapresource: Fetching complete mailbox  "INBOX"
akonadiagentbase_log: 57
57
log_imapresource: Fetching  3  intervals
Received:  57 In total:  57  Wanted:  57
log_imapresource: Retrieval complete. Elapsed(ms):  94
finished
log_imapresource: "INBOX"
log_kimap: "46 -FLAGS (\Seen)"
log_imapresource: "INBOX"
log_kimap: "50 -FLAGS (\Seen)"
log_imapresource: "INBOX"
log_kimap: "52 -FLAGS (\Seen)"
log_imapresource: "INBOX"
log_kimap: "53 -FLAGS (\Seen)"
log_imapresource: "INBOX"
log_kimap: "55 -FLAGS (\Seen)"
log_imapresource: ".INBOX"
log_kmail: Last resource finished syncing, mail check done