> GMail does not require STARTTLS.

    $ telnet smtp.gmail.com 587
    Trying 173.194.67.108...
    Connected to gmail-smtp-msa.l.google.com.
    Escape character is '^]'.
    220 mx.google.com ESMTP ea6sm27303065wib.5
    HELO zwp
    250 mx.google.com at your service
    AUTH PLAIN [elided]
    530 5.7.0 Must issue a STARTTLS command first. ea6sm27303065wib.5



    $ telnet smtp.gmail.com 587 
    Trying 173.194.67.109...
    Connected to gmail-smtp-msa.l.google.com.
    Escape character is '^]'.
    220 mx.google.com ESMTP ff2sm43397967wib.9
    HELO zwp
    250 mx.google.com at your service
    MAIL FROM:<test@example.com>
    530 5.7.0 Must issue a STARTTLS command first. ff2sm43397967wib.9