1 files changed, 3 insertions, 7 deletions
diff --git a/ishtar_common/utils.py b/ishtar_common/utils.py
index 56c6f669f..e293562ff 100644
--- a/ishtar_common/utils.py
+++ b/ishtar_common/utils.py
@@ -931,26 +931,22 @@ def get_urls_for_model(model, views, own=False, autocomplete=False,
     return urls
 
 
-HISTORY_M2M_SPLIT = u"*||*"
-
-
 def m2m_historization_changed(sender, **kwargs):
     obj = kwargs.get('instance', None)
     if not obj:
         return
-    hist_values = {}
+    hist_values = obj.history_m2m or {}
     for attr in obj.HISTORICAL_M2M:
         values = []
         for value in getattr(obj, attr).all():
             if not hasattr(value, "history_compress"):
                 continue
             values.append(value.history_compress())
-        hist_values['historical_' + attr] = HISTORY_M2M_SPLIT.join(values)
-    for key in hist_values:
-        setattr(obj, key, hist_values[key])
+        hist_values[attr] = values
     # force resave of last history record
     if hasattr(obj, 'skip_history_when_saving'):
         delattr(obj, 'skip_history_when_saving')
+    obj.history_m2m = hist_values
     obj._force_history = True
     q = obj.history.order_by("-history_date")
     if q.count():