title: Fatal error: Call to undefined function mb_split()
body: <p>When I try to install the Pagebuilder plugin for WordPress running on PHP5.4.33 I get the following error: </p>
  
  <p>Fatal error: Call to undefined function mb_split() in /home/***/public_html/mytheme/wp-content/plugins/page-builder/class/PB.PageBuilder.class.php on line 955 </p>
  
  <p>The full function in B.PageBuilder.class.php is as follows (see line 955 below)</p>
  
  <pre><code>function formatName($oName)
  {
      $nName=null;
      $data=mb_split('_',$oName);  /*** This is line 955 ***/
  
      foreach($data as $value) $nName.=ucfirst($value);
  
      return($nName);
  }
  </code></pre>
  
  <p>How can I fix this?</p>