> 	i've workarounded  the problem it by keeing _ctype_ as is, and tweaking
> 	lib/libc/locale/rune{,glue}.c.  does it look okay?
> 	in ctype.h nor lib/libc/gen/isctype.c.

Yeah, it seems to be fine.

What the people who currently have invalid locale table should do
is to replace the locale table to correct one which is 
((_ctype+1)[\t] & _B) == 0. Otherwise old static binaries don't
work properly.

> 	i really would like to see newer binaries use
> 	__CurrentRuneLocale.__runetype[] instead of _ctype_.  i'm not very
> 	happy about letting future programs to look at _ctype_.

No.
At least in ctype.h, we should keep to refer _ctype_[] rather than 
__CurrentRuneLocale.__runetype[] to keep _RuneLocale opaque.
Otherwise we lose flexibility to change implementation detail of
RuneLocale.
--
soda