Could someone please try the following and tell me whether they can
reproduce this bug?  I'm running 2.0 (the latest version, I presume, since
Windows Update doesn't suggest any 2.0 updates).  I've Googled for reports
on this, but I've found nothing.

Steps:

   1. Create a new WinForms (.NET 2.0) project in a relevant IDE (for
      example, Visual Studio 2005).
   2. Add a MenuStrip to the form.
   3. Add a top-level menu item with the text "&File" (without the
      quote characters).
   4. Create two menu items underneath this, "&New" and "&Open" (without
      the quote characters).
   5. Run the application.
   6. Press Alt+F, to open the File menu.
   7. Press the Down Arrow key.

Result:

   An ArithmeticException is raised.  Here are the details of the
   exception: <http://rafb.net/paste/results/ELOeJ371.html>.

Further info:

   This happens with any top-level menu item that has at least two
   sub-items.