Return Registered element when account exists (thanks to PioneerMike)

src/mod_register.erl

@@ -187,6 +187,18 @@ process_iq(From, To,
 			  sub_el = [SubEl, ?ERR_BAD_REQUEST]}
 	    end;
 	get ->
+	    {UsernameSubels, QuerySubels} =
+		case From of
+		    #jid{user = User, lserver = Server} ->
+			case ejabberd_auth:is_user_exists(User,Server) of
+			    true ->
+				{[{xmlcdata, User}], [{xmlelement, "registered", [], []}]};
+			    false ->
+				{[{xmlcdata, User}], []}
+			end;
+		    _ ->
+			{[], []}
+		end,
 	    IQ#iq{type = result,
 		  sub_el = [{xmlelement,
 			     "query",
@@ -197,8 +209,9 @@ process_iq(From, To,
 				   Lang,
 				   "Choose a username and password "
 				   "to register with this server")}]},
-			      {xmlelement, "username", [], []},
-			      {xmlelement, "password", [], []}]}]}
+			      {xmlelement, "username", [], UsernameSubels},
+			      {xmlelement, "password", [], []}
+			      | QuerySubels]}]}
     end.
 
 %% @doc Try to change password and return IQ response