diff --git a/CHANGES.txt b/CHANGES.txt
index f92418a..d48bb95 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -4,9 +4,13 @@ Changelog
 1.1 (Unreleased)
 ------------------
 
-- Added Afrikaans translations 
+- Added Afrikaans translations
   [jcbrand]
 
+- Fixed test failure for the default user portrait, which changed from
+  defaultUser.gif to defaultUser.png in Products.PlonePAS 4.0.5.
+  [maurits]
+
 1.0 (2011-02-07)
 ----------------
 
diff --git a/plone/app/discussion/tests/test_comments_viewlet.py b/plone/app/discussion/tests/test_comments_viewlet.py
index 2160605..35dea51 100644
--- a/plone/app/discussion/tests/test_comments_viewlet.py
+++ b/plone/app/discussion/tests/test_comments_viewlet.py
@@ -431,8 +431,12 @@ class TestCommentsViewlet(PloneTestCase):
         self.viewlet.update()
         portrait_url = self.viewlet.get_commenter_portrait('jim')
 
-        # Check if the correct default member image URL is returned
-        self.assertEquals(portrait_url, 'http://nohost/plone/defaultUser.gif')
+        # Check if the correct default member image URL is returned.
+        # Note that Products.PlonePAS 4.0.5 and later have .png and
+        # earlier versions have .gif.
+        self.failUnless(portrait_url in
+                        ('http://nohost/plone/defaultUser.png',
+                         'http://nohost/plone/defaultUser.gif'))
 
     def test_anonymous_discussion_allowed(self):
         # Anonymous discussion is not allowed by default