diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 51788c2bc..5efb43ae7 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,7 @@
+2009-07-25  Corinna Vinschen  <corinna@vinschen.de>
+
+	* posix.sgml (std-notes): Add flock restriction.
+
 2009-07-25  Corinna Vinschen  <corinna@vinschen.de>
 
 	* fhandler_console.cc (set_console_title): Set buffer size to
diff --git a/winsup/cygwin/posix.sgml b/winsup/cygwin/posix.sgml
index ee2b2a9c4..883edd251 100644
--- a/winsup/cygwin/posix.sgml
+++ b/winsup/cygwin/posix.sgml
@@ -1369,6 +1369,11 @@ Windows however.</para>
 and <function>clock_setres</function> only support CLOCK_REALTIME for
 now.</para>
 
+<para>BSD file locks created via <function>flock</function> are not
+propagated to the parent process and sibling processes.  The locks are
+only valid in the creating process and subsequently started child processes
+shaing the same file descriptor.</para>
+
 <para><function>fpclassify</function>, <function>isfinite</function>,
 <function>isgreater</function>, <function>isgreaterequal</function>,
 <function>isinf</function>, <function>isless</function>,