Problem with datagrid subcontrols (.NET 2003)

Hi all,

I have a problem (C#, .Net 2003). My datagrid has some listboxes. I need to get mouse X and Y on datagrid through OnMouseDown on that listboxes to put ListBox.SelectedIndex in datagrid[?][?]. DataGrid.HitTest recieves coordinates on DataGrid, but ot Datagrid's subcontrol.
Could you give me some help with it, or maybe some links, dedicated that problem.