Syscall 'isalpha()' is not acception national characters

[Lukas Zapletal]

Hello,

I have set Czech in Standards and formats in Reginal and Language
Options, Location also to Czech Republic and Keyboard to Czech in my
Windows XP Professional (English). The system function isalpha() do
not accept characters witch diacritics as alphanumeric characters and
programs which are not using UNICODE has a problem with that -- for
example Vim does not recognize word boundaries properly. On Czech
version of Windows XP its working as expected.

What setting am I missing? Do I have to set some environment variable
or something?

Thanks