Moving Cursor in DirectX Games

I am using the Wiimote and the .NET Wiimote lib to control a game (Borderlands specifically). I have all the controls worked out accept the Aiming (what the cursor is used for).

I have tried the following code without success:

[DllImport("User32.Dll")] public static extern long SetCursorPos(int x, int y);

And..

Cursor.Position = new Point(positionX, positionY);