title: Symfony2 default locale in routing
body: <p>I have a problem with routing and the internationalization of my site built with Symfony2.<br>
  If I define routes in the routing.yml file, like this: </p>
  
  <pre><code>example: 
      pattern:  /{_locale}/example 
      defaults: { _controller: ExampleBundle:Example:index, _locale: fr } 
  </code></pre>
  
  <p>It works fine with URLs like: </p>
  
  <pre><code>mysite.com/en/example 
  mysite.com/fr/example 
  </code></pre>
  
  <p>But doesn't work with </p>
  
  <pre><code>mysite.com/example 
  </code></pre>
  
  <p>Could it be that optional placeholders are permitted only at the end of an URL ?<br>
  If yes, what could be a possible solution for displaying an url like :  </p>
  
  <pre><code>mysite.com/example  
  </code></pre>
  
  <p>in a default language or redirecting the user to : </p>
  
  <pre><code>mysite.com/defaultlanguage/example 
  </code></pre>
  
  <p>when he visits :</p>
  
  <pre><code>mysite.com/example. ? 
  </code></pre>
  
  <p>I'm trying to figure it out but without success so far. </p>
  
  <p>Thanks.</p>