bootstrap多层模态框滚动条消失的问题

.modal-open .modal {overflow-x:hidden; overflow-y:auto}

<div class="modal fade" ... style="overflow: auto">

<div class="modal fade" id="myModal2" data-backdrop="static" <span style="color:#ff0000;">style="overflow:scroll"</span> 
    popover-page-id="CS040104"> 
    <div class="modal-dialog modal-1200"> 
      <div class="modal-content"> 
        <div class="modal-header"> 
          <button type="button" class="close" data-dismiss="modal" 
            aria-hidden="true">×</button> 
          <h4 class="modal-title" id="myModalLabel">模态框（Modal）标题222</h4> 
        </div> 
        <div class="modal-body" >在这里添加一些文本</div> 
        <div class="modal-footer"> 
          <button type="button" class="btn btn-suess" 
                 data-toggle="modal" target="modal" 
      data-target="#myModal3">模态框</button> 
          <button type="button" class="btn btn-default" data-dismiss="modal">关闭</button> 
          <button type="button" class="btn btn-primary">提交更改</button> 
        </div> 
      </div> 
      <!-- /.modal-content --> 
    </div> 
    <!-- /.modal --> 
    </div>