When you add a grid box to a form and set the "MousePointer" to a non default value and then run the form you get a C0000005 error when you move the mouse over the grid control.

Steps to reproduce:

1. Create a blank form
2. Add a grid control
3. Set the grid MousePointer = 1
4. Use any table so that the grid will show data.
5. Run the form
6. Wave your mouse around on the grid control for a few seconds.

You should get the C5 error within about 10 seconds or so.

Tested on Windows XP Pro with and without SP1.