diff --git a/ChangeLog b/ChangeLog
index 53d964f96c..a9e5d241ef 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu May  8 15:14:34 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* array.c (rb_ary_sort_bang): freeze temporary array.
+
 Thu May  8 13:19:18 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* vm.c (rb_thread_mark): mark stat_insn_usage only when ptr is not
diff --git a/array.c b/array.c
index 9df29447f1..9fe0fc9c1b 100644
--- a/array.c
+++ b/array.c
@@ -1513,13 +1513,16 @@ rb_ary_sort_bang(VALUE ary)
 	RBASIC(tmp)->klass = 0;
 	ruby_qsort(RARRAY_PTR(tmp), RARRAY_LEN(tmp), sizeof(VALUE),
 		   rb_block_given_p()?sort_1:sort_2, &RBASIC(tmp)->klass);
+	sort_reentered(&RBASIC(tmp)->klass);
 	RARRAY(ary)->ptr = RARRAY(tmp)->ptr;
 	RARRAY(ary)->len = RARRAY(tmp)->len;
 	RARRAY(ary)->aux.capa = RARRAY(tmp)->aux.capa;
 	FL_UNSET(ary, ELTS_SHARED);
 	RARRAY(tmp)->ptr = 0;
 	RARRAY(tmp)->len = 0;
+	RARRAY(tmp)->aux.capa = 0;
 	RBASIC(tmp)->klass = RBASIC(ary)->klass;
+	OBJ_FREEZE(tmp);
     }
     return ary;
 }