title: exec() command on mac osx returns 5
body: <p>I am trying to execute a thumbnail converter script phantomjs. 
  From my terminal it works fine but in my web page returns 5 code. Is that a problem with the permissions?  I am using php 5.3 + MAMP</p>
  
  <pre><code>            $output = array();
              $command = "./bundles/MainBundle/js/phantomjs /bundles/MainBundle/js/convert.js";
              $return_var=0;
              exec($command,$output,$return_var);
  </code></pre>
  
  <p>HELP! please</p>