title: getting HTTP Status 500 when location href or when forwarding from Servlet?
body: <p>I get this error:</p>
  
  <pre><code>HTTP Status 500 -
  </code></pre>
  
  <p>type Exception report</p>
  
  <p>message</p>
  
  <p>descriptionThe server encountered an internal error () that prevented it from fulfilling this request.</p>
  
  <p>exception</p>
  
  <p>org.apache.jasper.JasperException: java.lang.NullPointerException</p>
  
  <p>root cause</p>
  
  <p>java.lang.NullPointerException</p>
  
  <p>note The full stack traces of the exception and its root causes are available in the GlassFish Server Open Source Edition 3.1-b24 logs.
  GlassFish Server Open Source Edition 3.1-b24</p>
  
  <p>when I try to forward from a jsp to another jsp or when I forward in a servlet... The thing is that Y modify some datils from my page and I want to go back to the login-page and log in again to see if the update was successful !... Any ideas on this error ?... Thankx</p>