MUC: Fix traceback when requesting voice (fixes #1269) (thanks jonas’) Introduced by change from add_child to add_direct_child in ce57c69a20e2 Why does add_direct_child not return self like everything else?

module:log("error", "mod_pep_plus has been renamed to mod_pep, please update your config file. Auto-loading mod_pep...");
module:depends("pep");