diff --git a/ChangeLog b/ChangeLog
index b58d25b7c8..c5bc9b4e14 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Thu Jun  9 18:36:00 2011  Kenta Murata <mrkn@mrkn.jp>
+
+	* string.c: Fix the ambiguous description of the behavior of
+	  rb_str_aref_m with a range.  It returns nil when the beginning of
+	  the range is greater than the end of the string rather than the range.
+
 Thu Jun  9 10:57:03 2011  Aaron Patterson <aaron@tenderlovemaking.com>
 
 	* ext/psych/lib/psych/visitors/to_ruby.rb: Hash subclasses can be read
diff --git a/string.c b/string.c
index 0148d55be2..6722457486 100644
--- a/string.c
+++ b/string.c
@@ -3168,7 +3168,8 @@ rb_str_aref(VALUE str, VALUE indx)
  *  characters at offsets given by the range is returned. In all three cases, if
  *  an offset is negative, it is counted from the end of <i>str</i>. Returns
  *  <code>nil</code> if the initial offset falls outside the string, the length
- *  is negative, or the beginning of the range is greater than the end.
+ *  is negative, or the beginning of the range is greater than the end of the
+ *  string.
  *
  *  If a <code>Regexp</code> is supplied, the matching portion of <i>str</i> is
  *  returned. If a numeric or name parameter follows the regular expression, that