title: Configure ACTIVEMQ_OPTS in ActiveMQ 5.15.4
body: <p>I was trying to send an <code>ObjectMessage</code> containing a <code>myObject</code>, instance of <code>myClass</code>, using ActiveMQ as JMS Provider. Call to ActiveMQ is made through Mule 4.3.0.</p>
  <p>An error occurred in the receiving application:</p>
  <pre><code>Failed to build body from content. Serializable class not available to  broker. Reason: java.lang.ClassNotFoundException: Forbidden class client.MyClass! This class is not trusted to be serialized as ObjectMessage payload. Please take a look at http://activemq.apache.org/objectmessage.html for more information on how to configure trusted classes.
  </code></pre>
  <p>the page says:</p>
  <blockquote>
  <p>If you need to exchange object messages, you need to add packages your applications are using. You can do that with by using
  <code>org.apache.activemq.SERIALIZABLE_PACKAGES</code> system property of the
  broker. You can add this system property to <code>ACTIVEMQ_OPTS</code> variable in
  <code>${ACTIVEMQ_HOME}/bin/env</code> script.</p>
  </blockquote>
  <p>I am using ActiveMQ 5.15.4 . In the <code>\bin</code> subfolder, there is no <code>env</code> script, only the <code>activemq</code> script.</p>
  <p>Where should I configure <code>ACTIVEMQ_OPTS</code> so that I, will not get forbidden class error. Or if any alternative solutions will help.</p>