diff --git a/src/include/port/aix.h b/src/include/port/aix.h
index 1d50688d90f..30b9a18493b 100644
--- a/src/include/port/aix.h
+++ b/src/include/port/aix.h
@@ -1,3 +1,5 @@
+#  define USE_POSIX_TIME 
+#  define USE_POSIX_SIGNALS
 #  define CLASS_CONFLICT 
 #  define DISABLE_XOPEN_NLS 
 #  define HAVE_ANSI_CPP