--- a/plugins/mod_pubsub/pubsub.lib.lua	Wed Aug 01 19:18:07 2018 +0100
+++ b/plugins/mod_pubsub/pubsub.lib.lua	Wed Aug 01 19:18:25 2018 +0100
@@ -27,6 +27,7 @@
 	["invalid-options"] = { "modify", "bad-request", nil, "invalid-options" };
 	["forbidden"] = { "auth", "forbidden" };
 	["not-allowed"] = { "cancel", "not-allowed" };
+	["not-acceptable"] = { "modify", "not-acceptable" };
 	["internal-server-error"] = { "wait", "internal-server-error" };
 };
 local function pubsub_error_reply(stanza, error)