diff --git a/product/CMFActivity/ActivityTool.py b/product/CMFActivity/ActivityTool.py
index b22d262e7d41ddef3b9285183775f2424ea49410..904384d540276433761d6e3a67ac8182914dbb5a 100755
--- a/product/CMFActivity/ActivityTool.py
+++ b/product/CMFActivity/ActivityTool.py
@@ -92,7 +92,7 @@ class Message:
     return activity_tool.unrestrictedTraverse(self.object_path)
     
   def getObjectList(self, activity_tool):
-    if self.object_list is not None:
+    if self.object_list is None:
       try:
         expand_method_id = self.activity_kw['expand_method_id']
         obj = self.getObject(activity_tool)