Есть очень вредный п.14 - именно таким образом и появляются открытые релеи. Надо пользовать так (к сожалению, сил нет писать это по русски) - это кусок ФАКа:
=========
5.4. How do I allow selected clients to use this host as a relay? I
see that qmail-smtpd rejects messages to any host not listed in
control/rcpthosts.
Answer: Three steps. First, install tcp-wrappers, available separately,
including hosts_options. Second, change your qmail-smtpd line in
inetd.conf to
smtp stream tcp nowait qmaild /usr/local/bin/tcpd
/var/qmail/bin/tcp-env /var/qmail/bin/qmail-smtpd
(all on one line) and give inetd a HUP. Third, in tcpd's hosts.allow,
make a line setting the environment variable RELAYCLIENT to the empty
string for the selected clients:
tcp-env: 1.2.3.4, 1.2.3.5: setenv = RELAYCLIENT
Here 1.2.3.4 and 1.2.3.5 are the clients' IP addresses. qmail-smtpd
ignores control/rcpthosts when RELAYCLIENT is set. (It also appends
RELAYCLIENT to each envelope recipient address. See question 5.5 for
an
application.)
Alternative procedure, if you are using tcpserver 0.80 or above:
Create
/etc/tcp.smtp containing
1.2.3.6:allow,RELAYCLIENT=""
127.:allow,RELAYCLIENT=""
to allow clients with IP addresses 1.2.3.6 and 127.*. Run
tcprules /etc/tcp.smtp.cdb /etc/tcp.smtp.tmp < /etc/tcp.smtp
Finally, insert
-x /etc/tcp.smtp.cdb
after tcpserver in your qmail-smtpd invocation.
=========