disabling namespace in special-userdb on dovecot 2.2

[Marc]

Currently I have such special-userdb file

test:x:11111:22222:testaccount_descr:/home/users/testaccount:/bin/false:userdb_mail=mbox:~/mbox:INBOX=/home/users/testaccount/inbox:INDEX=/home/users/testaccount/index

However I am still getting errors of a default configured namespace that still seems to be active. Is there a way to disable this namespace or reconfigure this in the userdb file? (When I was testing this on a dovecot 2.3 I did not run into this)