qmail-inject control?

[mok swee loong]

hi all,

/var/qmail/control/rcpthosts can be use to restrict the the relaying from
smtp connection, but, how do i set restriction with program that invoke
qmail-inject directly?

i am having problem restricting mail sending out by php script that the php
binary will invoke the qmail-inject directly.

any thoughts?

regards,
mok