diff --git a/ChangeLog b/ChangeLog
index c649166b95..5331ddca68 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Wed Feb 15 19:52:28 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* ext/fiddle/closure.c (callback): same as r34506.
+
 Wed Feb 15 17:41:31 2012  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* io.c (io_strsetbuf): call rb_str_modify to make str independent
diff --git a/ext/fiddle/closure.c b/ext/fiddle/closure.c
index 962f9267fe..c601818ad4 100644
--- a/ext/fiddle/closure.c
+++ b/ext/fiddle/closure.c
@@ -125,7 +125,7 @@ callback(ffi_cif *cif, void *resp, void **args, void *ctx)
 	break;
 #if HAVE_LONG_LONG
       case TYPE_LONG_LONG:
-	*(unsigned LONG_LONG *)resp = rb_big2ull(ret);
+	*(unsigned LONG_LONG *)resp = NUM2ULL(ret);
 	break;
 #endif
       default:
diff --git a/test/fiddle/test_closure.rb b/test/fiddle/test_closure.rb
index 5878e72a70..381b3f96c1 100644
--- a/test/fiddle/test_closure.rb
+++ b/test/fiddle/test_closure.rb
@@ -55,5 +55,30 @@ module Fiddle
       n = 10000
       assert_equal(n, n.times {ObjectSpace.memsize_of(Closure.allocate)}, bug)
     end
+
+    %w[INT SHORT CHAR LONG LONG_LONG].each do |name|
+      type = DL.const_get("TYPE_#{name}") rescue next
+      size = DL.const_get("SIZEOF_#{name}")
+      [[type, size-1, name], [-type, size, "unsigned_"+name]].each do |t, s, n|
+        define_method("test_conversion_#{n.downcase}") do
+          arg = nil
+
+          clos = Class.new(Closure) do
+            define_method(:call) {|x| arg = x}
+          end.new(t, [t])
+
+          v = ~(~0 << (8*s))
+
+          arg = nil
+          assert_equal(v, clos.call(v))
+          assert_equal(arg, v, n)
+
+          arg = nil
+          func = Function.new(clos, [t], t)
+          assert_equal(v, func.call(v))
+          assert_equal(arg, v, n)
+        end
+      end
+    end
   end
 end if defined?(Fiddle)