/// <summary>
 /// Whenver we change presence, send the new presence to the room, including
 /// caps etc.
 /// </summary>
 /// <param name="sender"></param>
 /// <param name="pres"></param>
 private void m_stream_OnAfterPresenceOut(object sender, Presence pres)
 {
     Presence p = (Presence)pres.CloneNode(true);
     p.To = m_room;
     m_manager.Write(p);
 }