Can I do something like the Unix
"mail ... "
in Mac OS? Are there any plugins or modules to do this?
And if I have a mult-mail account in iMail, can I specify the sender account? I am not sure the default Mac iMail is related or not.
AFAIK osx comes with postfix as an smtpd, so if you configure that all should work like a normal *nix box.
EDIT: google turns out this http://hints.macworld.com/article.php?story=20081217161612647