title: StackOverflow like URL Routing
body: <p>Its my understanding that the questions in StackOverflow has the following format</p>
  
  <pre><code>http://stackoverflow.com/questions/{question-id}/{slug-made-from-question-title}
  </code></pre>
  
  <p>So basically the question is retrieved using the question-id. so whatever value I give the slug is  immaterial.</p>
  
  <p>First I would like to know whether this understanding is wrong :)</p>
  
  <p>I have a URL</p>
  
  <pre><code>http://stackoverflow.com/questions/6291678/convert-input-string-to-a-clean-readable-and-browser-acceptable-route-data
  </code></pre>
  
  <p>Then I changed the slug manually like this.</p>
  
  <pre><code>http://stackoverflow.com/questions/6291678/naveen
  </code></pre>
  
  <p>But it changed to the original slug. Firebug showed me a permenant redirect 301 on the altered URL. How to implement this functionality?</p>