diff --git a/ChangeLog b/ChangeLog
index 280cefe89e..452411303a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Jul 16 14:08:44 2009  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* array.c (rb_ary_sample): RDoc update.  a patch from Florian
+	  Frank.   [ruby-core:24347]
+
 Thu Jul 16 12:42:10 2009  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* ext/readline/readline.c (readline_readline): rl_free_line_state
diff --git a/array.c b/array.c
index 52981a2b4f..b9b60c8736 100644
--- a/array.c
+++ b/array.c
@@ -3526,9 +3526,11 @@ rb_ary_shuffle(VALUE ary)
  *     array.sample        -> obj
  *     array.sample(n)     -> an_array
  *
- *  Choose a random element, or the random +n+ elements, from the array.
- *  If the array is empty, the first form returns <code>nil</code>, and the
- *  second form returns an empty array.
+ *  Choose a random element or +n+ random elements from the array. The elements
+ *  are chosen by using random and unique indices into the array in order to
+ *  ensure that an element doesn't repeat itself unless the array already
+ *  contained duplicate elements. If the array is empty the first form returns
+ *  <code>nil</code> and the second form returns an empty array.
  *
  */