UNICODE and weird characters

I've build expat 2.0 with UNICODE. This uses internally UTF-16 and wchar_t.

When I use the parser, it sees all the tags, but the strings it reports 
contain weird (Chinese) characters. This is an example code:

void ModulesXMLParser::StartElementHandler(void *userData,
                                           const XML_Char *name,
                                           const XML_Char **atts)
{
    wxString xmlName(name);
    ...
}

Why do I see those Chinese characters (although my xml file contains 
simple characters)?