creating mailbox from imap

[Superbiji]

Hi,

I'm creating web based admin to add cyrus mailboxes.

But having problem because I'm using virtual domains
cyrus imap says Invalid mailbox name.

telnet localhost 143
* OK
. login postmaster bla
. OK User logged in
. create user/blabla at domain.com
. NO Invalid mailbox name
. create user/blabla%domain.com
. NO Invalid mailbox name
. create user/blabla#domain.com
. NO Invalid mailbox name

How to create user mailbox from imap without using cyradm.

Thanks