I might also suggest Mail::Mailer. Here is a proof-of-concept program for you to look at that acts as a Perl-based email transmission client:

#!/usr/bin/perl -w

use Mail::Mailer;

$smtp = Mail::Mailer->new("smtp","Server","smtp.server");

print "To:       ";
$to = <STDIN>;
chomp($to);
print "Subject:  ";
$subject = <STDIN>;
chomp($subject);
print "Body:\n";

while ($line = <STDIN>) {
    last if $line eq ".\n";
    $body .= $line;
}

chomp($body);

print "Opening SMTP connection...\n";
$smtp->open({
    "From" => "email\@example.com",
    "To" => $to,
    "Subject" => $subject
        });
print $smtp $body;
print "Sending email...\n";
$smtp->close() or die "Can't close mailer: $!";
print "Mail sent.\n";
[download]

Obviously, using strict is recommended.