diff --git a/themis/search/indexer.py b/themis/search/indexer.py
index d56eeca..a64f8aa 100644
--- a/themis/search/indexer.py
+++ b/themis/search/indexer.py
@@ -15,7 +15,7 @@ from themis.fields.vocabs import ContactsSource
 def mailDateIndexer(obj):
     if obj.portal_type not in ('courrier_entrant', 'courrier_sortant'):
         return None
-    for attr in ('date_reelle_courrier', 'date_reception'):
+    for attr in ('date_reelle_courrier', 'date_reception', 'date_envoi'):
         if not hasattr(obj, attr):
             continue
         if getattr(obj, attr):