title: Zend_Form - The mimetype of file 'foto.jpg' could not be detected
body: <p>I have a Zend_Form with file element like this:</p>
  
  <pre><code>-&gt;addElement('file', 'image', array(
          'required' =&gt; false,
          'label' =&gt; 'Venue Image',
          'validators' =&gt; array(
              array('IsImage', false),
              array('Size', false, '2097152'),
              array('Upload', false),
          ),
      ))
  </code></pre>
  
  <p>And when I'm using localhost the image is uploaded successfully. But when I move to my hosting the validation error shows for image field. The mimetype of file 'foto.jpg' could not be detected. What can be the reason of this?</p>