diff --git a/CHANGES.txt b/CHANGES.txt
index 75bb182..2b64f00 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,6 +1,14 @@
 Changelog
 =========
 
+1.0 (2011-01-24)
+----------------
+
+- Check if the current user has configured an e-mail address for the email 
+  notification option. This fixes http://dev.plone.org/plone/ticket/11428.
+  [timo]  
+
+
 1.0RC2 (2011-01-24)
 -------------------
 
diff --git a/plone/app/discussion/browser/comments.py b/plone/app/discussion/browser/comments.py
index 0c2a9e4..f7fd9c3 100644
--- a/plone/app/discussion/browser/comments.py
+++ b/plone/app/discussion/browser/comments.py
@@ -106,10 +106,17 @@ class CommentForm(extensible.ExtensibleForm, form.Form):
 
         registry = queryUtility(IRegistry)
         settings = registry.forInterface(IDiscussionSettings, check=False)
-        portal_membership = getToolByName(self.context, 'portal_membership')
+        mtool = getToolByName(self.context, 'portal_membership')
+        member = mtool.getAuthenticatedMember()
+        member_email = member.getProperty('email')
 
-        if not settings.user_notification_enabled or portal_membership.isAnonymousUser():
-            self.widgets['user_notification'].mode = interfaces.HIDDEN_MODE
+        # Hide the user_notification checkbox if user notification is disabled 
+        # or the user is not logged in. Also check if the user has a valid email
+        # address
+        if member_email == '' or \
+           not settings.user_notification_enabled or \
+           mtool.isAnonymousUser():
+                self.widgets['user_notification'].mode = interfaces.HIDDEN_MODE
 
     def updateActions(self):
         super(CommentForm, self).updateActions()
diff --git a/setup.py b/setup.py
index 1c8979a..71fd25a 100644
--- a/setup.py
+++ b/setup.py
@@ -1,7 +1,7 @@
 import sys
 from setuptools import setup, find_packages
 
-version = '1.0RC2'
+version = '1.0dev'
 
 install_requires = [
     'setuptools',