[Dovecot] Problems with namespaces

[tomzu at buu.lv]

Hi, I'm trying to create Shared folder with subfolders "SPAM" and
"NOT_Spam". Configuration: namespace public {   separator = /   prefix
= Shared/   location =
maildir:/vmail/%Ld/Shared:INDEX=/vmail/%Ld/%Ln/Shared   hidden = no }
Result I get (is exactly what I want): Inbox Drafts Sent Trash Shared
--NOT_Spam --SPAM I can select SPAM and NOT_Spam, delete messages etc,
but when I select "Shared", it shows: "Mailbox doesn't exist: Shared."
As a client I used OE and Thunderbird. How to get rid of that message?
I'm running latest Dovecot release 1.1.2 /Tom