diff --git a/actionpack/test/controller/request_test.rb b/actionpack/test/controller/request_test.rb
index 82ddfec..4f0b06b 100644
--- a/actionpack/test/controller/request_test.rb
+++ b/actionpack/test/controller/request_test.rb
@@ -480,12 +480,37 @@ class UrlEncodedRequestParameterParsingTest < Test::Unit::TestCase
   def test_deep_query_string_with_array_of_hashes_with_multiple_pairs
     assert_equal(
       {'x' => {'y' => [{'z' => '10', 'w' => 'a'}, {'z' => '20', 'w' => 'b'}]}},
       ActionController::AbstractRequest.parse_query_parameters('x[y][][z]=10&x[y][][w]=a&x[y][][z]=20&x[y][][w]=b')
     )
   end
+  
+  def test_deep_query_string_with_nested_arrays
+    # This works; when building the first hash at y[0], it keeps adding
+    # key-value pairs to the same hash until a key is repeated ('z'), causing
+    # a second hash to be created at y[1].
+    assert_equal(
+      {'y' => [{'z' => '1', 'w' => '2'}, {'z' => '3', 'w' => '4'}]},
+      ActionController::AbstractRequest.parse_query_parameters('y[][z]=1&y[][w]=2&y[][z]=3&y[][w]=4')
+    )
+
+    # But this doesn't work; after creating the sub-array ('y'), subsequent
+    # values that should be added to x[0]['y'] are instead added to a new
+    # array in a new hash, x[1]['y'].
+    assert_equal(
+      {'x' => [{'y' => [{'z' => '1', 'w' => '2'}]}]},
+      ActionController::AbstractRequest.parse_query_parameters('x[][y][][z]=2&x[][y][][w]=1')
+    )
+    
+    # This doesn't work either.
+    assert_equal(
+      {'x' => [{'y' => [{'z' => '1', 'w' => '2'}, {'z' => '3', 'w' => '4'}]}]},
+      ActionController::AbstractRequest.parse_query_parameters(
+        'x[][y][][z]=2&x[][y][][w]=1&x[][y][][z]=3&x[][y][][w]=4')
+    )
+  end
 
   def test_query_string_with_nil
     assert_equal(
       { "action" => "create_customer", "full_name" => ''},
       ActionController::AbstractRequest.parse_query_parameters(@query_string_with_empty)
     )