diff --git a/include/wx/platform.h b/include/wx/platform.h
index 2d9c7d6a3c..91f11101ec 100644
--- a/include/wx/platform.h
+++ b/include/wx/platform.h
@@ -152,7 +152,10 @@
 #   endif
 #endif /* wxUSE_UNICODE */
 
-
+#if defined( __MWERKS__ ) && !defined(__INTEL__)
+// otherwise MSL headers bring in WIN32 dependant APIs
+#undef UNICODE
+#endif
 /*
    some compilers don't support iostream.h any longer, while some of theme
    are not updated with <iostream> yet, so override the users setting here