I Have a Problem on Qmail Anti-Relaying

[Seyyed Hamid Reza Hashemi Golpayegani]

Hi ,

I have installed Redhar Linux 6.0 and qmail 1.03 on it . I have install POP3
daemen on that . OutLook Express and other pop3 clients can send a message
that have a sender e-mail address that not on my domain.com . For example if
my domain is morva.com you can send a mail message from my PoP3 daemon
that's sender address is from hotmail.com !?!?!?
I want to deliver only the mails that from my domain and reject mails that
don't from my domain ! So how can I do this on my pop3 and sending mechanism
?

Thanx
Hamid Hashemi
Tehran - Iran