diff --git a/src/applications/draft/storage/PhabricatorVersionedDraft.php b/src/applications/draft/storage/PhabricatorVersionedDraft.php
--- a/src/applications/draft/storage/PhabricatorVersionedDraft.php
+++ b/src/applications/draft/storage/PhabricatorVersionedDraft.php
@@ -58,7 +58,7 @@
     return id(new PhabricatorVersionedDraft())
       ->setObjectPHID($object_phid)
       ->setAuthorPHID($viewer_phid)
-      ->setVersion($version)
+      ->setVersion((int)$version)
       ->save();
   }