bootstrap: change modal backdrop opacity only for specific modals

I have a menu with multiple modals. When I open one over another it turns backgrount into black, which is ugly. I understand that I need change filter: alpha(opacity=80); in .modal-backdrop.fade.in in bootstrap.css. But I need to change it not for all modals, only for some of them. Here's the html code for first modal

    <div class="modal hide" id="mbusModal">
        <div class="modal-header">
            <button type="button" class="close" data-dismiss="modal">×</button>
            <h3>MBUS</h3>
        </div>
        <div class="modal-body">
            <form class="form-horizontal">
                <form class="well form-inline">
                    <input type="button" class="btn" onclick="$('#dinMbusModal').modal('show'); $('#tabsMbusDin a:last').tab('show');" value="din">
                </form>
            </div>
        <div class="modal-footer">
            <a href="#" class="btn" data-dismiss="modal">Закрыть</a>
            <a href="#" class="btn btn-primary" onclick="addPort('mbus',$('#mbusDev').val(),$('#mbusSpeed').val()); $('#mbusModal').modal('hide')">Применить</a>
        </div>

This modal needs to change his backdrop:

    <div class="modal hide" id="dinMbusModal" style="width: 500px; margin: -250px 0 0 -250px;">
        <div class="modal-header">
            <button type="button" class="close" data-dismiss="modal">×</button>
            <h3>DIN</h3>
        </div>
        <div class="modal-body">
        </div>
        <div class="modal-footer">
            <a href="#" class="btn" data-dismiss="modal">Закрыть</a>
            <a href="#" class="btn btn-primary" onclick="addPort('din_mbus',,); $('#dinMbusModal').modal('hide')">Применить</a>
        </div>
    </div>