S: * OK m28s05 Cyrus IMAP4 v2.1.18-IPv6-Debian-2.1.18-1 server ready
C: C01 CAPABILITY
S: * CAPABILITY IMAP4 IMAP4rev1 ACL QUOTA LITERAL+ MAILBOX-REFERRALS NAMESPACE UIDPLUS ID NO_ATOMIC_RENAME UNSELECT CHILDREN MULTIAPPEND SORT THREAD=ORDEREDSUBJECT THREAD=REFERENCES IDLE STARTTLS ANNOTATEMORE
S: C01 OK Completed