title: Symfony Upload doc, docx file using sfValidatorFile Mime type issue
body: <p>I am using sfValidatorFile class to allow user to upload pdf or document in symfony 1.4.
  But It's not working with document, It returns mime type octet-stream which prevent to upload the document. </p>
  
  <p>I have tried with the solution provided <a href="https://stackoverflow.com/questions/2104127/uploaded-docx-files-turning-into-zip">here</a>!</p>
  
  <p>But unfortunately it's not working. Here is my code.</p>
  
  <pre><code>'my_filename' =&gt; new sfValidatorFile(
                array ('required'=&gt;false,
                       'mime_type_guessers' =&gt; array('guessFromFileinfo'),
                       'mime_types' =&gt;  array ( 'application/pdf',
                                                'application/msword',
                                                'application/vnd.openxmlformats-
                                                officedocument.wordprocessingml.document',                
                                                    'application/vnd.ms-word',
                                                    'application/x-msword',
                                                    'application/msword;     charset=binary')) ,
                  array( 'mime_types'=&gt; 'only doc, docx and pdf files are allowed' )),
  </code></pre>
  
  <p>Also tried with msValidatorFile class solution provided on same link, but it allows to upload zip and rar too.</p>
  
  <p>Is there any way to allow only pdf and documents to upload?</p>