Status off virtual domains with kolab2 !

[I.BIN.DAHAM]

Hello all,
i am wondering that the virtual domain support isn't working right now 
with kolab2.
I read all documentations about kolab2.
My Server is working fine only in single domain mode.
So i want to build up Multi Domain support. My server is a free art and 
music server - low budget.
So there are a lot of domains to manage.
I find the interaction between kolab and cyrus very usefull so i tried 
to migrate.
But i stopped on the virtual domain support.
There's only on line in the imapd.conf that mention the availability of 
virtual domain support.
But how are the managed in ldap ?
If i have a top level domain like: dc=test,dc=com, where is the virtual 
domain relatively settled ?

My example:
TOP: dc=test,dc=com
Virt: ou=domain1,dc=test,dc=com.

But it's not working.
Have i to creat completely separated top level domain ?
dc=example,dc=com. etc.

Can anyone tell my how i have to confiugre a new virtual domain in my 
ldap tree ?
I would be fine to hear from you.

Thanks in advance

IBIN