title: Get the Orginal url
body: <p>I am rewriting the URL, In that I want to get the original url.when user request the below url:
  <strong>http://test.acom/test12.htm</strong> the original url of this request is below</p>
  
  <p><strong>http://test.acom/cms.aspx?pid=123</strong> when </p>
  
  <p>now I want to find out the original url
  how can I got that, please guide me.</p>