diff --git a/boards/models/attachment/__init__.py b/boards/models/attachment/__init__.py
--- a/boards/models/attachment/__init__.py
+++ b/boards/models/attachment/__init__.py
@@ -42,6 +42,10 @@ class AttachmentManager(models.Manager):
 class Attachment(models.Model):
     objects = AttachmentManager()
 
+    class Meta:
+        app_label = 'boards'
+        ordering = ('id',)
+
     file = models.FileField(upload_to=get_upload_filename, null=True)
     mimetype = models.CharField(max_length=50, null=True)
     hash = models.CharField(max_length=36, null=True)