Subject => $self->{subject},
'Message-ID' => '<' . $self->_create_message_id . '>',
'X-Mailer' => "kivitendo " . SL::Version->get_version,
Subject => $self->{subject},
'Message-ID' => '<' . $self->_create_message_id . '>',
'X-Mailer' => "kivitendo " . SL::Version->get_version,