In the same way that the Hello, LocalAddr, and LocalPort options are passed through to Net::SMTP when the helo, localaddr, and localport attributes are set in Email::Sender::Transport::SMTP, it should also be possible to specify the Domain option for Net::SMTP. Net::SMTP passes this value straight through to IO::Socket, and as far as I can tell, this is the only reliable way to enforce IPv4 connections.
In the same way that the
Hello,LocalAddr, andLocalPortoptions are passed through to Net::SMTP when thehelo,localaddr, andlocalportattributes are set in Email::Sender::Transport::SMTP, it should also be possible to specify theDomainoption for Net::SMTP. Net::SMTP passes this value straight through to IO::Socket, and as far as I can tell, this is the only reliable way to enforce IPv4 connections.