Symfony and Zend Lucene Error

I use symfony with Zend Lucene Search. I have

$query = Zend_Search_Lucene_Search_QueryParser::parse($query.'*');
$hits = self::getLuceneIndex()->find($query);

Sometimes I have error :

At least 3 non-wildcard characters are required at the beginning of pattern.

When I make like in documentations:

$pattern = new Zend_Search_Lucene_Index_Term($query.'*');
$query = new Zend_Search_Lucene_Search_Query_Wildcard($pattern);
$hits = self::getLuceneIndex()->find($query);

It finds nothing.

I do not is it right , but it is work for me :

So, query fail in my case, because it have < 3 characters or have some special characters, so in my search action :

 public function executeAds(sfWebRequest $request)
  {
      if (!$query = $request->getParameter('query'))
    {
      return $this->forward('search', 'adssearch');
    }

   $query = str_replace(" ", "", $query);
   $query = preg_replace("/[^A-Za-z0-9]/","",$query);
    if (strlen(trim($query))<3)

    {
         $this->redirect('search/notice');
    }

    $this->ads = Doctrine_Core::getTable('Ads') ->getAdsLuceneQuery($query); 

I do not use

$pattern = new Zend_Search_Lucene_Index_Term($query.'*');
$query = new Zend_Search_Lucene_Search_Query_Wildcard($pattern);
$hits = self::getLuceneIndex()->find($query);

Because it is not work for me.