* elmo2.el (elmo-imap4-bye-error): Define.

* elmo2.el (elmo-imap4-bye-error): Define.

* elmo-imap4.el (elmo-imap4-response-bye-p): New macro.
(elmo-imap4-response-error-text): Get text from BYE response.
(elmo-imap4-read-response): Return if BYE response.
(elmo-imap4-accept-ok): Cause elmo-imap4-bye-error when BYE response.
(elmo-imap4-folder-exists-p): Ditto.
(elmo-imap4-commit): Do nothing when different mailbox is selected.
(elmo-imap4-parse-bye): New function.
(elmo-imap4-parse-response): Remove needless let.
Call `elmo-imap4-parse-bye'.