my $mailfile_data;
if ( ! open(MAILFILE, "$mailfile") ) {
    Log( "Unable to open $mailfile for email report." );
    return FAILURE;
}

{
    local $/;
    undef $/;
    $mailfile_data = <MAILFILE>;
}

close MAILFILE;

$email->attach(
    Type        => "text/html",
    Data        => $mailfile_data,
    Disposition => "inline",
);