Hi Winan,
You might take a look at the following line:
http://www.palomine.net/qmail/relaying.htmlThe gentleman that wrote the article about FAQ 5.4 seem to know alot about qamil. He includes his email in this article and invites questions. Based on what I read, he discourages SMTP security by obscurity by changing the defualt SMTP port 25. There seem to be better solutions.