diff --git a/weboob/applications/qhavedate/contacts.py b/weboob/applications/qhavedate/contacts.py
index df0d8681..d758d435 100644
--- a/weboob/applications/qhavedate/contacts.py
+++ b/weboob/applications/qhavedate/contacts.py
@@ -67,6 +67,8 @@ class ThreadMessage(QFrame):
 
 
     def __eq__(self, m):
+        if not isinstance(m, Message):
+            return False
         return self.message == m.message
 
 class ContactThread(QWidget):
diff --git a/weboob/capabilities/messages.py b/weboob/capabilities/messages.py
index 292977f0..5ba0ce75 100644
--- a/weboob/capabilities/messages.py
+++ b/weboob/capabilities/messages.py
@@ -117,6 +117,9 @@ class Message(_Message):
             return '%s.%s' % (self.thread.id, self._parent_id)
 
     def __eq__(self, msg):
+        if not isinstance(msg, Message):
+            return False
+
         if self.thread:
             return unicode(self.thread.id) == unicode(msg.thread.id) and \
                    unicode(self.id) == unicode(msg.id)