thomas.mertes@t-mobile.at wrote:
RtlUpperChar does not take the locale into account. It always convertes just 'a' .. 'z' and nothing else.
Is this the right direction or did I miss something?
No, that's not right. We really need to convert to unicode first, then upper case unicode character and convert the result back to ansi. See the ReactOS source for reference (at the first glance it closely enough matches NTDLL asm code).