When adding a custom event without the attribute exit_code it can not be deleted with JOC

<?xml version="1.0" encoding="UTF-8"?>
<actions>
  <action name="MyEventHandler">
    <events>
      <event_group group="myGroup" logic="not myEvent">
        <event event_class="myClass" event_id="myid" event_name="myEvent" />
      </event_group>
    </events>
    <commands>
      <add_event>
        <event event_class="myClass" event_id="myId" scheduler_event_expiration_period="00:15" />
      </add_event>
    </commands>
  </action>
</actions>