diff --git a/ChangeLog b/ChangeLog
index 972c46f2ac..a89c7ead53 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Dec  3 02:56:34 2008  Yusuke Endoh  <mame@tsg.ne.jp>
+
+	* test/ruby/test_rational.rb: add a test.
+
 Wed Dec  3 02:53:24 2008  Yusuke Endoh  <mame@tsg.ne.jp>
 
 	* test/ruby/test_range.rb: add a test.
diff --git a/test/ruby/test_rational.rb b/test/ruby/test_rational.rb
index 5758749d5e..4c031b9848 100644
--- a/test/ruby/test_rational.rb
+++ b/test/ruby/test_rational.rb
@@ -129,6 +129,9 @@ class Rational_Test < Test::Unit::TestCase
     assert_raise(ArgumentError){Rational(Object.new)}
     assert_raise(ArgumentError){Rational()}
     assert_raise(ArgumentError){Rational(1,2,3)}
+
+    assert_equal(Complex(Rational(1, 2), Rational(1, 2)), Rational(Complex(1, 1), Complex(2, 0)))
+    assert_instance_of(Numeric, Rational.class_eval { convert(Numeric.new) })
   end
 
   def test_attr