If you compare the MailNotifyBody
templates in "mailnotify.tmpl" and "mailnotify.nat.tmpl" you will see that the latter has an extra space prior to the "From:" header. This extra space causes SMTP (non-SendMail) notifications to fail with the following error:
ERROR: Can't send mail, missing 'From:' at /var/www/wiki/lib/TWiki/Net.pm line 262.
is not forthcoming about the internal error; the only symptom is that mail notifications don't work!
Removed the space char. Hope that fixes the problem in the latest NatSkin