Presumably this depends on how you're trying to authenticate. The released smtpmail doesn't have starttls support, for instance.
Why use it on Ubuntu, though? If exim is set up correctly, Emacs' sendmail method (the default) will DTRT.
Presumably this depends on how you're trying to
authenticate. The released smtpmail doesn't have
starttls support, for instance.
Why use it on Ubuntu, though? If exim is set up
correctly, Emacs' sendmail method (the default)
will DTRT.