diff --git a/src/include/stdbool.h b/src/include/stdbool.h
index 7324f4b3..fca59bca 100644
--- a/src/include/stdbool.h
+++ b/src/include/stdbool.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: stdbool.h,v 1.2 1999/09/24 23:09:09 espie Exp $ */
+/* $OpenBSD: stdbool.h,v 1.3 2004/10/02 12:55:31 espie Exp $ */
 
 /*
  * Written by Marc Espie, September 25, 1999
@@ -8,6 +8,14 @@
 #ifndef	_STDBOOL_H_
 #define	_STDBOOL_H_	
 
+#ifndef __cplusplus
+
+#if defined(__GNUC__) && __GNUC__ >= 3
+/* Support for _C99: type _Bool is already built-in. */
+#define false	0
+#define true	1
+
+#else
 /* `_Bool' type must promote to `int' or `unsigned int'. */
 typedef enum {
 	false = 0,
@@ -18,9 +26,18 @@ typedef enum {
 #define	false	false
 #define	true	true
 
+#endif
+
 /* User visible type `bool' is provided as a macro which may be redefined */
 #define bool _Bool
 
+#else /* __cplusplus */
+#define _Bool 	bool
+#define bool 	bool
+#define false 	false
+#define true 	true
+#endif /* __cplusplus */
+
 /* Inform that everything is fine */
 #define __bool_true_false_are_defined 1