imap client that supports passing authorization id

[mat]

> I am not aware of any.  Neither am I aware of any that support IMAP ACLs
> [settings, viewing, etc...] or SIEVE.  Very sad.
>
> If someone else knows of any I'd love to hear about it.
Sure. シ

It seems that KMail4 can cope with IMAP ACLs 
(<http://docs.kde.org/stable/en/kdepim/kmail/folders.html>, go for "Access 
Control tab"); KMail3 also had an rudimentary Sieve support (see 
<http://docs.kde.org/stable/en/kdepim/kmail/faq.html#idp12463536>), don't 
know how that looks in (stable) KMail4 now.
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