--- a/plugins/smacks.lua	Sun Jun 06 16:43:36 2021 +0200
+++ b/plugins/smacks.lua	Thu Jun 10 11:58:23 2021 +0200
@@ -80,7 +80,7 @@
 				end
 				stream:debug("Received ack: New ack: "..new_ack.." Last ack: "..last_ack.." Unacked stanzas now: "..#outgoing_queue.." (was "..old_unacked..")");
 				last_ack = new_ack;
-			else
+			elseif new_ack < last_ack then
 				stream:warn("Received bad ack for "..new_ack.." when last ack was "..last_ack);
 			end
 		elseif stanza.name == "enabled" then