Ciao a tutti, ho modificato MDaemon dicendo di utilizzare il server SMTP di google nel caso in cui ci siano problemi ... e quando invio mail a tiscali:

Sat 2010-10-30 17:23:53: Attempting SMTP connection to [209.85.227.109:587]
Sat 2010-10-30 17:23:53: Waiting for socket connection...
Sat 2010-10-30 17:23:53: * Connection established (mio_ip:3829 -> 209.85.227.109:587)
Sat 2010-10-30 17:23:53: Waiting for protocol to start...
Sat 2010-10-30 17:23:53: <-- 220 mx.google.com ESMTP p4sm2450672wej.4
Sat 2010-10-30 17:23:53: --> EHLO company.mail
Sat 2010-10-30 17:23:53: <-- 250-mx.google.com at your service, [mio_ip]
Sat 2010-10-30 17:23:53: <-- 250-SIZE 35651584
Sat 2010-10-30 17:23:53: <-- 250-8BITMIME
Sat 2010-10-30 17:23:53: <-- 250-STARTTLS
Sat 2010-10-30 17:23:53: <-- 250 ENHANCEDSTATUSCODES
Sat 2010-10-30 17:23:53: --> MAIL From:<mioindirizzomail@dominio.it> SIZE=1123
Sat 2010-10-30 17:23:53: <-- 530 5.7.0 Must issue a STARTTLS command first. p4sm2450672wej.4
Sat 2010-10-30 17:23:53: --> QUIT