diff --git a/ChangeLog b/ChangeLog
index 28c713c627..fd49cfcc62 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Mon Aug 24 21:31:37 2009  Kouhei Sutou  <kou@cozmixng.org>
+
+	* lib/rss/maker/base.rb, test/rss/test_maker_2.0.rb: fix a bug
+	that RSS Maker doesn't accept 'false' as guid's isPermaLink.
+	Reported by Joe Holt. Thanks!!!
+
 Mon Aug 24 18:58:56 2009  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* include/ruby/missing.h (vsnprintf): rollback a part of r24179, because
diff --git a/lib/rss/maker/base.rb b/lib/rss/maker/base.rb
index 9ccfba7e84..5d795443a4 100644
--- a/lib/rss/maker/base.rb
+++ b/lib/rss/maker/base.rb
@@ -238,7 +238,7 @@ module RSS
             setter = "#{var}="
             if target.respond_to?(setter)
               value = __send__(var)
-              if value
+              unless value.nil?
                 target.__send__(setter, value)
                 set = true
               end
diff --git a/test/rss/test_maker_2.0.rb b/test/rss/test_maker_2.0.rb
index d4d9832373..705270df4e 100644
--- a/test/rss/test_maker_2.0.rb
+++ b/test/rss/test_maker_2.0.rb
@@ -508,6 +508,26 @@ module RSS
       assert_equal(content, guid.content)
     end
 
+    def test_guid_permanent_link_false
+      content = "http://inessential.com/2002/09/01.php#a2"
+
+      rss = RSS::Maker.make("2.0") do |maker|
+        setup_dummy_channel(maker)
+        setup_dummy_item(maker)
+
+        guid = maker.items.last.guid
+        assert_equal(nil, guid.permanent_link?)
+        assert_equal(guid.isPermaLink, guid.permanent_link?)
+        guid.permanent_link = false
+        assert_equal(false, guid.permanent_link?)
+        assert_equal(guid.isPermaLink, guid.permanent_link?)
+        guid.content = content
+      end
+      guid = rss.channel.items.last.guid
+      assert_equal(false, guid.isPermaLink)
+      assert_equal(content, guid.content)
+    end
+
     def test_not_valid_guid
       content = "http://inessential.com/2002/09/01.php#a2"