title: PHP Warning - Unable to initialize module
body: <p>My webpage is running really slow and I wanted to check error log and it is full with this error - </p>
  
  <pre><code>[11-Dec-2012 09:52:54 Europe/Helsinki] PHP Warning:  PHP Startup: rar: Unable to initialize module
  Module compiled with module API=20060613
  PHP    compiled with module API=20090626
  These options need to match
  in Unknown on line 0
  </code></pre>
  
  <p>What is it? Can anyone know how to fix it? My site is running Joomla.</p>