diff --git a/ChangeLog b/ChangeLog
index 92d747dd21..7f065332d9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,7 @@
 Wed Apr 24 21:51:13 2013  Tanaka Akira  <akr@fsij.org>
 
 	* configure.in: Check mblen().
+	  mblen() is optional in uClibc.
 
 	* eval_intern.h (CharNext): Don't use mblen() is not available.