+// in wxMSW version 2.1.11 and earlier, wxIcon always derives from wxBitmap,
+// but this is very dangerous because you can mistakenly pass an icon instead
+// of a bitmap to a function taking "const wxBitmap&" - which will *not* work
+// because an icon is not a valid bitmap
+//
+// Starting from 2.1.12, you have the choice under this backwards compatible
+// behaviour (your code will still compile, but probably won't behave as
+// expected!) and not deriving wxIcon class from wxBitmap, but providing a
+// conversion ctor wxBitmap(const wxIcon&) instead.
+//
+// Recommended setting: 0
+#define wxICON_IS_BITMAP 0
+