HTTPASYNC-64: race conditions in async caching module (release notes)

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpasyncclient/trunk@1561694 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/RELEASE_NOTES.txt b/RELEASE_NOTES.txt
index 312c2e8..819d339 100644
--- a/RELEASE_NOTES.txt
+++ b/RELEASE_NOTES.txt
@@ -1,6 +1,9 @@
 Changes since 4.0
 -------------------
 
+* [HTTPASYNC-64] Race conditions in async caching module.
+  Contributed by Oleg Kalnichevski <olegk at apache.org>
+
 * [HTTPASYNC-65] Relaxed OSGi dependency import version ranges
   Contributed by Christian Schneider <chris at die-schneider.net>