Magento Controller Dispatch doesn't render

I followed this tutorial: blog.baobaz.com/en/blog/magento-module-create-your-own-controller but it doesn't work for me. My files:

/app/etc/modules/Baobaz_Arithmetic.xml

<?xml version="1.0" ?>
<config>
<modules>
    <Baobaz_Arithmetic>
        <active>true</active>
        <codePool>local</codePool>
    </Baobaz_Arithmetic>
</modules>
</config>

/app/code/local/Baobaz/Arithmetic/etc/config.xml file:

<?xml version="1.0" ?>
<config>
<modules>
    <Baobaz_Arithmetic>
        <version>0.1.0</version>
    </Baobaz_Arithmetic>
</modules>
<frontend>
    <routers>
        <arithmetic>
            <use>standard</use>
            <args>
                <module>Baobaz_Arithmetic</module>
                <frontName>arithmetic</frontName>
            </args>
        </arithmetic>
    </routers>   
</frontend>
</config>

/app/code/local/Baobaz/Arithmetic/controllers/IntegerController.php

<?php
 class Baobaz_Arithmetic_IntegerController extends Mage_Core_Controller_Front_Action {
  public function multiplyAction(){
    echo "Respect my authoritah";
  }
 }
?>

I cleared the cache. When calling (...).com/arithmetic/integer/multiply I get 404 page. I run Magento 1.8.1.

How to fix this?