freeswitch/conf/directory/default/1016.xml

<include>
  <user id="1016" mailbox="1016">
    <params>
      <param name="password" value="1234"/>
    </params>
    <variables>
      <variable name="user_context" value="default"/>
      <variable name="effective_caller_id_name" value="Extension 1016"/>
      <variable name="effective_caller_id_number" value="1016"/>
    </variables>
  </user>
</include>