diff --git a/include/common/syscall.h b/include/common/syscall.h
index a3b27eb..3ccbf5a 100644
--- a/include/common/syscall.h
+++ b/include/common/syscall.h
@@ -2,7 +2,7 @@
  * include/common/syscall.h
  * Redefinition of some missing OS-specific system calls.
  *
- * Copyright 2000-2011 Willy Tarreau <w@1wt.eu>
+ * Copyright 2000-2012 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
@@ -124,6 +124,21 @@
 #endif /* $arch */
 #endif /* __NR_splice */
 
+/* accept4() appeared in Linux 2.6.28, but it might not be in all libcs. Some
+ * archs have it as a native syscall, other ones use the socketcall instead.
+ */
+#ifndef __NR_accept4
+#if defined(__x86_64__)
+#define __NR_accept4            288
+#elif defined(__sparc__) || defined(__sparc64__)
+#define __NR_splice             323
+#else
+#define ACCEPT4_USE_SOCKETCALL    1
+#ifndef SYS_ACCEPT4
+#define SYS_ACCEPT4              18
+#endif /* SYS_ACCEPT4 */
+#endif /* $arch */
+#endif /* __NR_accept4 */
 
 #endif /* __linux__ */
 #endif /* _COMMON_SYSCALL_H */