diff --git a/Include/unicodeobject.h b/Include/unicodeobject.h
index 6c492d1..44c1775 100644
--- a/Include/unicodeobject.h
+++ b/Include/unicodeobject.h
@@ -109,6 +109,10 @@
 # endif
 #endif
 
+#if defined(MS_WINDOWS) && defined(HAVE_USABLE_WCHAR_T)
+#  define HAVE_MBCS
+#endif
+
 #ifdef HAVE_WCHAR_H
 /* Work around a cosmetic bug in BSDI 4.x wchar.h; thanks to Thomas Wouters */
 # ifdef _HAVE_BSDI
@@ -1162,7 +1166,7 @@
     );
 #endif
 
-#ifdef MS_WIN32
+#ifdef HAVE_MBCS
 
 /* --- MBCS codecs for Windows -------------------------------------------- */
 
@@ -1191,7 +1195,7 @@
     );
 #endif
 
-#endif /* MS_WIN32 */
+#endif /* HAVE_MBCS */
 
 /* --- Decimal Encoder ---------------------------------------------------- */