win32 and UNICODE

I'm trying to use log4cxx in a win32 Unicode project and am having some
difficulties.  If I don't #define UNICODE, the log4cxx::String is a
basic_string<char> (because windows uses _UNICODE).  If I do #define
UNICODE, then I get:

c:\chrome\ice\client\code\cpp\internal\include\log4cxx\helpers\tchar.h(1
07) : error C2371: 'TCHAR' : redefinition; different basic types


The code in tchar.h looks like this:

#ifndef TCHAR
        typedef wchar_t TCHAR;

Shouldn't that be #ifndef __TCHAR_DEFINED (or perhaps _TCHAR_DEFINED)?

Sean Rohead