z-index for Drag and Drop

Hello. Is it possible to have a grid (A) with two other grids floating over it (B & C) using higher CSS.z-index and drag and drop from B to C?

When I drag from B to C, it appears to be dragging into A instead. Also, the tooltip of the dragging item appears behind B & C.

You can specify any necessary z-index value in dhtmlxgrid.css

.dragSpanDiv{     font-size : 12px;     border: 1px gray solid; background-color:white;
      z-index:99; // this line can be added

>>it appears to be dragging into A instead
The d-n-d routine based on mouse position in moment of drag , so if mouse was moved other grid B - it must be set as drop target.
If changing z-index will not solve problem with incorrect drop - please provide any kind of sample where problem can be reconstructed ( you can send it directly to support@dhtmlx.com )