Add HAVE_MKTIME
diff --git a/Mac/Include/config.h b/Mac/Include/config.h
index fd10a04..bc33a0a 100644
--- a/Mac/Include/config.h
+++ b/Mac/Include/config.h
@@ -46,6 +46,7 @@
 #define HAVE_FOPENRF
 #endif
 
+#define HAVE_MKTIME
 #ifdef __MWERKS__
 #define HAVE_STRFTIME
 #ifndef __MC68K__