my $smtp = Net::SMTP->new('$my_host');
die "error connecting to $my_host" unless defined $smtp;

$smtp->mail($ENV{USER}) or die "error issuing MAIL command: ".$smtp->message();

...

##</code><code>##

telnet mysmtphost.com 25
HELO myip
MAIL FROM: myemail@abc.com
RCPT TO: recipient@xyz.com
DATA
helo there
blah blah
.