diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index c069b28c3..109f5e6ac 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,7 @@
+2009-04-26  Yaakov Selkowitz  <yselkowitz@users.sourceforge.net>
+
+	* include/cygwin/socket.h: Define SOL_IPV6.
+
 2009-04-21  Corinna Vinschen  <corinna@vinschen.de>
 
 	* ctype.cc (__set_ctype): Copy exact part of the current active
diff --git a/winsup/cygwin/include/cygwin/socket.h b/winsup/cygwin/include/cygwin/socket.h
index fdb842dc6..44b11b75a 100644
--- a/winsup/cygwin/include/cygwin/socket.h
+++ b/winsup/cygwin/include/cygwin/socket.h
@@ -198,6 +198,7 @@ struct OLD_msghdr
 
 /* Setsockoptions(2) level. Thanks to BSD these must match IPPROTO_xxx */
 #define SOL_IP		0
+#define SOL_IPV6	41
 #define SOL_IPX		256
 #define SOL_AX25	257
 #define SOL_ATALK	258