diff --git a/Mac/mwerks/mwerks_nonshared_config.h b/Mac/mwerks/mwerks_nonshared_config.h
index b6414f4cddc..dc73e92e6f8 100644
--- a/Mac/mwerks/mwerks_nonshared_config.h
+++ b/Mac/mwerks/mwerks_nonshared_config.h
@@ -20,7 +20,7 @@
 /* #define USE_MAC_SHARED_LIBRARY	/* Enable code to add shared-library resources */
 /* #define USE_MAC_APPLET_SUPPORT	/* Enable code to run a PYC resource */
 /* #define USE_MAC_DYNAMIC_LOADING		/* Enable dynamically loaded modules */
-/* #define USE_MALLOC_DEBUG			/* Enable range checking and other malloc debugging */
+#define USE_MALLOC_DEBUG			/* Enable range checking and other malloc debugging */
 #define USE_GDBM		/* Include the gdbm module */
 #define USE_ZLIB		/* Include the zlib module */
 #ifdef __powerc