[Dovecot] How dovecot treats UTF8 mailbox names in sieve scripts and `namespace' section

[Igor Zinovik]

  Hello.

I read on upgrading page that one can use UTF8 mailbox names for
plugins.  As i understand i do not need to convert UTF8 names to mUTF-7
and can use raw UTF8 in plugins section, e.g.:
/etc/dovecot/dovecot.conf
...
plugin {
        ...
        # Autocreate \Spam folder
        autocreate = Спам
        autosubscribe = Спам
...

But what about sieve scripts and other configuration sections:
1. Do i need to convert UTF8 mailbox names in `namespace' section?
namespace inbox {
        ...
        mailbox &BCEEPwQwBDw- {
            special_use = \Junk
        }

2. Do i need to convert UTF8 mailbox names in sieve scripts?
/etc/dovecot/dovecot_before.sieve
...
require ["reject","fileinto"];

# Put all spam into separete IMAP folder
if header :contains "X-Spam-Flag" "YES" {
        fileinto "&BCEEPwQwBDw-";
}