I would check if a remote server on port 25 is accepting STARTTLS for email using php , how can I do it ?
(I other words I should do this
telnet domain.com 25
Connected to domain.com.
Escape character is '^]'.
EHLO t220-hostname.domain.com ESMTP Exim 4.69 #1 Mon, 06 Feb 2012 08:26:08 -0500
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
250-hostname.domain.com Hello localhost [18.104.22.168]
250-AUTH PLAIN LOGIN
via php , is it possible ? )