diff --git a/addons/mail/mail_thread.py b/addons/mail/mail_thread.py
index 1378aabd3ee..33cc5481108 100644
--- a/addons/mail/mail_thread.py
+++ b/addons/mail/mail_thread.py
@@ -199,7 +199,7 @@ class mail_thread(osv.AbstractModel):
         ], context=context)
         for fol in fol_obj.browse(cr, uid, fol_ids, context=context):
             thread_subtype_dict = res[fol.res_id]['message_subtype_data']
-            for subtype in fol.subtype_ids:
+            for subtype in [st for st in fol.subtype_ids if st.name in thread_subtype_dict]:
                 thread_subtype_dict[subtype.name]['followed'] = True
             res[fol.res_id]['message_subtype_data'] = thread_subtype_dict