--- a/plugins/mod_register.lua Mon Jan 11 10:13:02 2010 +0000 +++ b/plugins/mod_register.lua Mon Jan 11 17:52:28 2010 +0500 @@ -141,7 +141,7 @@ username = nodeprep(table.concat(username)); password = table.concat(password); local host = module.host; - if not username then + if not username or username == "" then session.send(st.error_reply(stanza, "modify", "not-acceptable", "The requested username is invalid.")); elseif usermanager_user_exists(username, host) then session.send(st.error_reply(stanza, "cancel", "conflict", "The requested username already exists."));