i've setup smtp but
hi everyone,i've setup mailenable smtp and pop server software. i have also installed the JMail asp component. In the my SMTP security settings i have denied access to all relay accept the list i specify and i have added 127.0.0.1 in the list.
when i send a email via the JMail component and use the IP address of 127.0.0.1 in the script, the emails seem to get delivered smoothly. However, if i use mail.mydomain.com i get errors relating to authentication
can anyone tell me how exactly the smtp validates scripts sending mail. does it mean: the fact that i have allowed relay to 127.0.0.1 only scripts running locally and connecting through 127.0.0.1 will gain access?
i am new to SMTP so please can someone give me a good explanation about how its working coz at the moment everything is working but it is all coincidental and i dont know exactly why it is working, i would prefer to know exactly why its working at least that way if something goes wrong i know how to fix it

a simple lingo explanation would be very much appreciated.
cheers