Tk MouseWheel Support

[Richard Holmes]

I am trying to use the mouse wheel to scroll a list box, but I'm not
getting the event. When I bind "<Button-1>" to the listbox I get the
event and I'm able to scroll using yview_scroll. I've tried binding
"MouseWheel" and "<MouseWheel>", and I've also tried "<Button-4>" and
"<Button-5>" even though I'm using Windows (XP, if that makes a
difference). None of these works (I'm using print to see if I got to
an event handler, and there's no printout).

TIA for any help!

Dick