помогите настроить postfix
чтоб пользователь мог извне при авторизации использовать мой smtp сервер для отправки почты в инет

вот мой main.cf

readme_directory = /usr/share/doc/postfix/README_FILES
html_directory = /usr/share/doc/postfix/html
sendmail_path = /usr/sbin/sendmail.postfix
setgid_group = postdrop
command_directory = /usr/sbin
manpage_directory = /usr/share/man
daemon_directory = /usr/lib/postfix
data_directory = /var/lib/postfix
newaliases_path = /usr/bin/newaliases
mailq_path = /usr/bin/mailq
queue_directory = /var/spool/postfix
mail_owner = postfix
myhostname = doman.su
mydomain = doman.su
# User configurable parameters
home_mailbox=Maildir/
mailbox_size_limit = 0
message_size_limit = 15726840
inet_interfaces = all
mynetworks = 127.0.0.0/8
mynetworks_style = subnet
#delay_warning_time = 4h
smtpd_banner = $myhostname ESMTP $mail_name ($mail_version) (Mandriva Linux)
mydestination = domen.su
unknown_local_recipient_reject_code = 450
smtp-filter_destination_concurrency_limit = 2
lmtp-filter_destination_concurrency_limit = 2
disable_vrfy_command = yes
receive_override_options = no_address_mappings
smtp_sasl_security_options = noanonymous
smtpd_sasl_auth_enable = yes
smtpd_use_tls = yes
smtpd_sasl_security_options =
smtpd_sasl_local_domain = $myhostname
smtpd_sasl_exceptions_networks = $mynetworks
smtpd_client_restrictions = permit_sasl_authenticated
smtpd_sender_restrictions = permit_sasl_authenticated, permit_mynetworks
broken_sasl_auth_clients = yes
smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination, reject_rbl_client list.dsbl.org, reject_rbl_client relays.ordb.org, reject_rbl_client dynablock.wirehub.net, reject_rbl_client blackholes.wirehub.net, reject_rbl_client dnsbl.njabl.org
relay_domains =