diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7c7ab5c79..9011e9dc0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,8 @@ rebar.config: fix mochiweb git url
 
 tag emqtt release accoding to [Semantic Versioning](http://semver.org/)
 
+max clientId length is 1024 now.
+
 0.2.0 (2014-12-07)
 -------------------