diff --git a/include/common/ebtree.h b/include/common/ebtree.h
index 854666ab5..1a5ce8650 100644
--- a/include/common/ebtree.h
+++ b/include/common/ebtree.h
@@ -1,6 +1,6 @@
 /*
  * Elastic Binary Trees - generic macros and structures.
- * (C) 2002-2007 - Willy Tarreau <w@1wt.eu>
+ * (C) 2002-2008 - Willy Tarreau <w@1wt.eu>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -307,13 +307,23 @@ static inline int fls64(unsigned long long x)
  * this in inline functions, because the code reordering it causes very often
  * has a negative impact on the calling functions.
  */
-#if __GNUC__ < 3 && !defined(__builtin_expect)
+#if !defined(likely)
+#if __GNUC__ < 3
 #define __builtin_expect(x,y) (x)
-#endif
-
-#ifndef likely
+#define likely(x) (x)
+#define unlikely(x) (x)
+#elif __GNUC__ < 4
+/* gcc 3.x does the best job at this */
 #define likely(x) (__builtin_expect((x) != 0, 1))
 #define unlikely(x) (__builtin_expect((x) != 0, 0))
+#else
+/* GCC 4.x is stupid, it performs the comparison then compares it to 1,
+ * so we cheat in a dirty way to prevent it from doing this. This will
+ * only work with ints and booleans though.
+ */
+#define likely(x) (x)
+#define unlikely(x) (__builtin_expect((x), 0))
+#endif
 #endif
 
 /* Support passing function parameters in registers. For this, the
diff --git a/include/common/standard.h b/include/common/standard.h
index 248bbe91b..162a9ebc0 100644
--- a/include/common/standard.h
+++ b/include/common/standard.h
@@ -2,7 +2,7 @@
   include/common/standard.h
   This files contains some general purpose functions and macros.
 
-  Copyright (C) 2000-2007 Willy Tarreau - w@1wt.eu
+  Copyright (C) 2000-2008 Willy Tarreau - w@1wt.eu
   
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
@@ -46,13 +46,24 @@
  * helps the compiler produce the most compact critical paths, which is
  * generally better for the cache and to reduce the number of jumps.
  */
+#if !defined(likely)
 #if __GNUC__ < 3
 #define __builtin_expect(x,y) (x)
-#endif
-
+#define likely(x) (x)
+#define unlikely(x) (x)
+#elif __GNUC__ < 4
+/* gcc 3.x does the best job at this */
 #define likely(x) (__builtin_expect((x) != 0, 1))
 #define unlikely(x) (__builtin_expect((x) != 0, 0))
-
+#else
+/* GCC 4.x is stupid, it performs the comparison then compares it to 1,
+ * so we cheat in a dirty way to prevent it from doing this. This will
+ * only work with ints and booleans though.
+ */
+#define likely(x) (x)
+#define unlikely(x) (__builtin_expect((x), 0))
+#endif
+#endif
 
 /*
  * copies at most <size-1> chars from <src> to <dst>. Last char is always
diff --git a/include/proto/task.h b/include/proto/task.h
index 6bee1b2f1..49e3a94b6 100644
--- a/include/proto/task.h
+++ b/include/proto/task.h
@@ -55,7 +55,7 @@ static inline struct task *__task_wakeup(struct task *t)
 	DLIST_ADD(run_queue, &t->qlist);
 	t->state = TASK_RUNNING;
 
-	if (likely(t->wq)) {
+	if (likely(t->wq != NULL)) {
 		tree_delete(t->wq);
 		t->wq = NULL;
 	}
diff --git a/src/backend.c b/src/backend.c
index 037885074..4c5eec3dd 100644
--- a/src/backend.c
+++ b/src/backend.c
@@ -786,7 +786,7 @@ static struct server *fwrr_get_next_server(struct proxy *p)
 	fwrr_queue_srv(srv);
 
  requeue_servers:
-	if (unlikely(full)) {
+	if (unlikely(full != NULL)) {
 		if (switched) {
 			/* the tree has switched, requeue all extracted servers
 			 * into "init", because their place was lost, and only
diff --git a/src/ev_epoll.c b/src/ev_epoll.c
index a0c48b108..326d5a42e 100644
--- a/src/ev_epoll.c
+++ b/src/ev_epoll.c
@@ -142,7 +142,7 @@ REGPRM2 static void alloc_chg_list(const int fd, int old_evt)
 {
 	struct fd_chg *ptr;
 
-	if (unlikely(chg_ptr[fd]))
+	if (unlikely(chg_ptr[fd] != NULL))
 		return;
 
 #if LIMIT_NUMBER_OF_CHANGES
diff --git a/src/task.c b/src/task.c
index 7f6e0e7a2..c60961f3a 100644
--- a/src/task.c
+++ b/src/task.c
@@ -68,7 +68,7 @@ struct task *task_queue(struct task *task)
 		task->qlist.p = NULL;
 	}
 
-	if (unlikely(task->wq)) {
+	if (unlikely(task->wq != NULL)) {
 		tree_delete(task->wq);
 		task->wq = NULL;
 	}