The current Security (Use a Secure Connection) settings are:-
  Never
  Whenever Possible
  Always

These actually map to
  No security (OK, thats what it says)
  SMTP with STARTTLS
  SMTP over SSL

This is both confusing and very non-obvious, and should be changed to 2
orthogonal settings:-
  Security Type:
     - SMTP with STARTTLS
     - SMTP over SSL      (OK these can be better worded)

and a "Use a Secure Connection" as at present, except now the options would mean:-
   - Never - don't do security
   - Whenever Possible - do encryption if offered, don't complain if not.
       NB for SSMTP connections this makes no sense, so behave same as "Always"
   - Always - do encryption, refuse connection if not offered/accepted/possible


Other information: