diff --git a/common.cfg b/common.cfg
index faf2ab9c50a7aa47b1d1d9e2b7087819cdb5e0dd..cc651cee6056e85b79a2352e47ce6999d4167f0e 100644
--- a/common.cfg
+++ b/common.cfg
@@ -15,7 +15,8 @@ django-rest-swagger = >2.1
 django-guardian = >=1.4,<2.0
 djangorestframework = >3.7
 django-activity-stream = >= 0.6.5
-django-jsonfield = >= 1.0.1
+django-jsonfield = >=1.0.1
+django-post-office = <3.3
 jsonfield = <3.0
 
 [scripts]