sub send_receipts {
    <snip>

    $sender = new Mail::Sender
        {smtp => $Mailserver, from => 'CS Handin <kendal>'};
    $sender->MailMsg({to => "$userid\@keele.ac.uk",
        replyto => $handin_manager,
        subject => 'Receipt for work handed in',
        msg => $body});
    $sender->Close;
}