diff --git a/test/ruby/test_rational.rb b/test/ruby/test_rational.rb
index d94ded3fe3..5ca5478f24 100644
--- a/test/ruby/test_rational.rb
+++ b/test/ruby/test_rational.rb
@@ -560,7 +560,7 @@ class Rational_Test < Test::Unit::TestCase
     assert_equal([Rational(2.2),Rational(1)], Rational(1).coerce(2.2))
     assert_equal([Rational(2),Rational(1)], Rational(1).coerce(Rational(2)))
 
-    assert_nothing_raised(TypeError, '[Bug #5020] [ruby-devl:44088]') do
+    assert_nothing_raised(TypeError, '[Bug #5020] [ruby-dev:44088]') do
       Rational(1,2).coerce(Complex(1,1))
     end
   end