[exim] Blocking local users

Здравствуйте,

How can i block local users from sending mail via command line and
smtp?

i've tried
deny senders = username : username@??? : lsearch;/etc/localspamusers

or i should use perl func to check it?

-- 
С уважением,
 Коваленко Иван, Элвис-Телеком           mailto:kig@telekom.ru