diff --git a/test/should_receive_test.rb b/test/should_receive_test.rb
index 9c4906c..f9ff117 100644
--- a/test/should_receive_test.rb
+++ b/test/should_receive_test.rb
@@ -504,11 +504,11 @@ def test_arg_matching_with_regex_matching_non_string
 
   def test_arg_matching_with_class
     FlexMock.use do |m|
-      m.should_receive(:hi).with(Fixnum).returns(10)
+      m.should_receive(:hi).with(Integer).returns(10)
       m.should_receive(:hi).with(Object).returns(20)
 
       assert_equal 10, m.hi(319)
-      assert_equal 10, m.hi(Fixnum)
+      assert_equal 10, m.hi(Integer)
       assert_equal 20, m.hi("hi")
     end
   end