Prevent posting into an archived thread

boards/models/post/manager.py

@@ -36,6 +36,9 b' class PostManager(models.Manager):'
         Creates new post
         """
 
+        if thread is not None and thread.is_archived():
+            raise Exception('Cannot post into an archived thread')
+
         if not utils.is_anonymous_mode():
             is_banned = Ban.objects.filter(ip=ip).exists()
         else: