diff --git a/ChangeLog b/ChangeLog
index cf88c30aa2..addbbf30b5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun May  4 14:29:14 2008  Tanaka Akira  <akr@fsij.org>
+
+	* eval.c (rb_obj_respond_to): check the result of respond_to? method
+	  by RTEST.
+
 Sun May  4 12:57:58 2008  Tanaka Akira  <akr@fsij.org>
 
 	* string.c (rb_str_each_line): return original string.
diff --git a/eval.c b/eval.c
index ab2c33dbcb..e5c8d47fe2 100644
--- a/eval.c
+++ b/eval.c
@@ -454,7 +454,7 @@ rb_obj_respond_to(VALUE obj, ID id, int priv)
 	args[n++] = ID2SYM(id);
 	if (priv)
 	    args[n++] = Qtrue;
-	return rb_funcall2(obj, respond_to, n, args);
+	return RTEST(rb_funcall2(obj, respond_to, n, args));
     }
 }
 
diff --git a/test/ruby/test_string.rb b/test/ruby/test_string.rb
index c71be7d09d..70214c8ff5 100644
--- a/test/ruby/test_string.rb
+++ b/test/ruby/test_string.rb
@@ -1403,4 +1403,12 @@ class TestString < Test::Unit::TestCase
       s1 << 'a'
     }
   end
+
+  def test_respond_to
+    o = Object.new 
+    def o.respond_to?(arg) [:to_str].include?(arg) ? nil : super end
+    def o.to_str() "" end
+    def o.==(other) "" == other end
+    assert_equal(false, "" == o)
+  end
 end