ncursesw: KEY_* and collisions with unicode chars

[Felix Natter]

hello,

a user of GTypist reported that he cannot enter a Polish character
because it will be interpreted as backspace (KEY_BACKSPACE):

> I noticed that it is not possible to input one of the Polish diacritic
> letters 'c with acute' (unicode 0x107 = 263) because it interferes
> with KEY_BACKSPACE defined in ncurses.h (0407 = 263)

How can I tell the difference between KEY_BACKSPACE and unicode
0x107 (or can I teach ncursesw to return 0x8 for backspace)?

The 'get_wch' manpage mentions KEY_CODE_YES, but IMHO this is just
a bit that is set is a wchar_t contains a KEY_*, thus colliding with
unicode 0x107.

Thanks!
-- 
Felix Natter