diff --git a/test/ruby/test_m17n_comb.rb b/test/ruby/test_m17n_comb.rb
index 3a37ed4a23..f66a74e280 100644
--- a/test/ruby/test_m17n_comb.rb
+++ b/test/ruby/test_m17n_comb.rb
@@ -1635,4 +1635,8 @@ class TestM17NComb < Test::Unit::TestCase
     }
   end
 
+  def test_bug11486
+    bug11486 = '[Bug #11486]'
+    assert_nil ("\u3042"*19+"\r"*19+"\u3042"*20+"\r"*20).encode("euc-jp").gsub!(/xxx/i, "")
+  end
 end