diff --git a/ChangeLog b/ChangeLog
index 811dfa7d4f..aa54d61137 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2006-10-25  Ulrich Drepper  <drepper@redhat.com>
+
+	* sysdeps/gnu/netinet/tcp.h: Define TCP_CONGESTION.
+
 2006-10-18  Ulrich Drepper  <drepper@redhat.com>
 
 	* configure.in: Disable building profile libraries by default.
diff --git a/manual/conf.texi b/manual/conf.texi
index ef00db6b7b..605e305071 100644
--- a/manual/conf.texi
+++ b/manual/conf.texi
@@ -1454,11 +1454,6 @@ Inquire about the value of @code{_POSIX_ASYNC_IO}.
 @item _PC_PRIO_IO
 Inquire about the value of @code{_POSIX_PRIO_IO}.
 
-@comment unistd.h
-@comment POSIX.1g
-@item _PC_SOCK_MAXBUF
-Inquire about the value of @code{_POSIX_PIPE_BUF}.
-
 @comment unistd.h
 @comment LFS
 @item _PC_FILESIZEBITS
diff --git a/sysdeps/gnu/netinet/tcp.h b/sysdeps/gnu/netinet/tcp.h
index 87099ec14a..2c04ec9b7f 100644
--- a/sysdeps/gnu/netinet/tcp.h
+++ b/sysdeps/gnu/netinet/tcp.h
@@ -49,6 +49,7 @@
 #define TCP_WINDOW_CLAMP 10	/* Bound advertised window */
 #define TCP_INFO	 11	/* Information about this connection. */
 #define	TCP_QUICKACK	 12	/* Bock/reenable quick ACKs.  */
+#define TCP_CONGESTION	 13	/* Congestion control algorithm.  */
 
 #ifdef __USE_MISC
 # include <sys/types.h>