[Dovecot] sieve delivery to utf folders

[Nikita Koshikov]

Hello list,

Today, my users have noticed, that delivery to folders with non-english names is broken. For example, if I create russian directory, it correct encoded and display into mail-client program and my webmail:
Encoded:		Normal view
.INBOX.&BEIENQRBBEI-	русс

This is part of sieve script, which routing delivery to russian folder. 
....
elsif allof (header :contains "Subject" "qwe")
{
        fileinto "INBOX/&BEIENQRBBEI-";
}

But, when actualy delivery take place, in logs I have

Jul 30 17:13:49 deliver(koshikov.n at domain.com): Info: sieve: msgid=<4A71A9E6.5040301 at domain.com>: stored mail into mailbox 'INBOX/&-BEIENQRBBEI-

And folder .INBOX.&-BEIENQRBBEI- appears in users maildir. This folder can't be unencoded by mail-client program and user see exactly "&-BEIENQRBBEI-" under INBOX directory(also normaly encoded directory "&BEIENQRBBEI-" --> "русс" displays correct). Something breaks encoding and adds sing "-" to all words in utf encoded directory names.

I can't tell exactly when this problem appear, but I remember that I have tested delivery to russian directories by sieve scripts and all worked fine.

My current dovecot installation is 1.2.2, dovecot-sieve-0.1.9 and managesieve-0.11.7