title: Stacktrace from Camel Context onException
body: <p>I'm trying to retrieve the stacktrace from the onException handler in Apache Camel:</p>
  
  <pre><code>   &lt;onException&gt;
              &lt;exception&gt;java.lang.Exception&lt;/exception&gt;
              &lt;handled&gt;
                  &lt;constant&gt;true&lt;/constant&gt;
              &lt;/handled&gt;
  
              &lt;setHeader headerName="exception"&gt;
                  &lt;simple&gt;${exception}&lt;/simple&gt;
              &lt;/setHeader&gt;
     &lt;/onException&gt;
  </code></pre>
  
  <p>However, the above only shows the exception rather than the entire stacktrace.</p>
  
  <p>I understand that Camel stores the caught exception as a property on the Exchange with the key: Exchange.EXCEPTION_CAUGHT, but how can this be retrieved from the camel context routes file ?</p>