- if usermanager_user_exists(username, session.host) then
- session.send(st.error_reply(stanza, "cancel", "conflict"));
+ local host = module.host;
+ 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."));