problem with virtualdomain

[JOYDEEP]

dear list,

I am really fade up and need your kind guidance to solve this cyrus-imap
problem.

here is my  imapd.conf

---------------------------------------------------
configdirectory: /var/lib/imap
partition-default: /vmail/domains
sievedir: /var/lib/sieve
sendmail: /usr/sbin/sendmail

admins: cyrus
allowanonymouslogin: no
allowplaintext: yes
sasl_pwcheck_method: saslauthd
sasl_mech_list: PLAIN LOGIN
sasl_minimum_layer: 0

autocreatequota: 10000
reject8bit: no
quotawarn: 90
timeout: 30
poptimeout: 10
dracinterval: 0
drachost: localhost

lmtp_overquota_perm_failure: no
lmtp_downcase_rcpt: yes
lmtpsocket:  /var/lib/imap/socket/lmtp
unixhierarchysep: yes
virtdomains: userid
defaultdomain: opendingo.com
hashimapspool: true

servername: lvps87­230­8­228.opendingo.com
-------------------------------------------------------

1> now if I change "virtdomains: userid"  to "virtdomains: yes"  I can't
create any mailbox with cm command.
it reports  "permissions denied". I have flipped through the log but no
log reports about this .

2> with "virtdomains: userid" I can create user like " cm
user.test at kolkata.in" but felamimail reports users mailbox does not exist.

please help.
thanks