> So I would read from this that the OP has either fallen foul of the
> US-ASCII fallback (e.g. no langinfo.h when building under Cygwin), or
> else his environment has explicitly picked US-ASCII.

Somebody mentions on http://bugs.python.org/issue3824 that:
"And nl_langinfo(CODESET) is useless on cygwin because it's always US-
ASCII."

And here: http://svn.xiph.org/trunk/vorbis-tools/intl/localcharset.c
"Cygwin 2006 does not have locales.  nl_langinfo (CODESET) always
returns "US-ASCII"."

If I understood you right, this could cause the problems I
encountered.

Cygwin 1.7 is currently in beta. Maybe this improves things in this
respect?

Regards,
Thomas.