title: Magento not writing to log files
body: <p>My Magento installation suddenly stopped writing to log files.
  If I try to output the following:</p>
  
  <pre><code>Mage::log('Test', null, 'test.log');
  </code></pre>
  
  <p>Magento creates this file but it's empty.</p>
  
  <p>Logging is activated in settings -> developer.</p>