[Dovecot] Virtual - thread refs for labeled message

[Łukasz]

Hi

I hope you will understand my problem.
I want to make virtual folder called "Virtual/label1-threads". This 
folder should have:
1. messages labeled fe. $label1 from INBOX
and
2. messages from Sent folder inthread refs with those labeled.

message1 <-- $label1 INBOX
|----message2 <- Sent
------|-----message3 <- INBOX
.....

Can anyone help me with this?

-- 
Łukasz