diff --git a/acconfig.h b/acconfig.h
index 654f0119..75350596 100644
--- a/acconfig.h
+++ b/acconfig.h
@@ -11,6 +11,7 @@
 #undef HAVE_PL_PERL
 #undef HAVE_STATIC_PERL
 #undef HAVE_GMODULE
+#undef WANT_BIG5
 
 /* macros/curses checks */
 #undef HAS_CURSES