--- a/mod_http_upload/mod_http_upload.lua	Sun Jan 29 17:31:28 2017 +0100
+++ b/mod_http_upload/mod_http_upload.lua	Sun Jan 29 17:32:40 2017 +0100
@@ -87,7 +87,7 @@
 
 	local random;
 	repeat random = uuid();
-	until lfs.mkdir(join_path(storage_path, random))
+	until lfs.mkdir(join_path(storage_path, random)) or not lfs.attributes(join_path(storage_path, random, filename))
 
 	pending_slots[random.."/"..filename] = origin.full_jid;
 	local base_url = module:http_url();