USE_GUSI2 should be defined, not USE_GUSI1.
diff --git a/Mac/mwerks/mwerks_plugin_config.h b/Mac/mwerks/mwerks_plugin_config.h
index 1630c6c..4e23a64 100644
--- a/Mac/mwerks/mwerks_plugin_config.h
+++ b/Mac/mwerks/mwerks_plugin_config.h
@@ -2,8 +2,8 @@
** Config file for dynamically-loaded ppc/cfm68k plugin modules.
*/
-#define USE_GUSI1 /* Stdio implemented with GUSI */
-/* #define USE_GUSI2 /* Stdio implemented with GUSI */
+/* #define USE_GUSI1 /* Stdio implemented with GUSI */
+#define USE_GUSI2 /* Stdio implemented with GUSI */
#define WITH_THREAD /* Use thread support (needs GUSI 2, not GUSI 1) */
#define USE_MSL /* Use MSL libraries */
#ifdef USE_MSL