freeswitch/conf/directory/default/1000.xml

<include>
  <user id="1000" mailbox="1000">
    <params>
      <param name="password" value="mypass"/>
      <param name="vm-password" value="1234"/>
      <!--<param name="vm-mailto" value="me@mydomain.com"/>-->
      <!--<param name="vm-email-all-messages" value="true"/>-->
    </params>
    <variables>
      <variable name="user_context" value="default"/>
    </variables>
  </user>
</include>