diff --git a/mac/otnet.c b/mac/otnet.c
index eb24b85c..1033961d 100644
--- a/mac/otnet.c
+++ b/mac/otnet.c
@@ -2,6 +2,10 @@
  * Macintosh OpenTransport networking abstraction
  */
 
+#if TARGET_API_MAC_CARBON
+#define OTCARBONAPPLICATION 1
+#endif
+
 #include <OpenTransport.h>
 #include <OpenTptInternet.h>