[Dovecot] Dovecot IMAP is broken after upgrade from 2.1.2 to 2.1.3

[Michael Neubert]

> And what happens without SSL? e.g. telnet localhost 143

Without SSL it is no problem:

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telnet imap-server 143
Trying xxx.xxx.xxx.xxx...
Connected to imap-server.
Escape character is '^]'.
* OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE 
IDLE STARTTLS AUTH=PLAIN] Dovecot ready.
a login "username" "password"
a OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE 
IDLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS MULTIAPPEND 
UNSELECT CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE 
QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS 
SPECIAL-USE QUOTA] Logged in
b select inbox
* FLAGS (\Answered \Flagged \Deleted \Seen \Draft nonjunk $Forwarded)
* OK [PERMANENTFLAGS (\Answered \Flagged \Deleted \Seen \Draft nonjunk 
$Forwarded \*)] Flags permitted
[...]
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