I use a Hahnal battery grip with my d300 and have had no problems until now. Whilst everything works with regard to the dials and the shutter on the grip, including the IR remote, the battery is not recognised in the panel. When I go to the menu and battery info, it only shows the battery fitted in the camera. I've done the obvious and checked the contacts in the battery holder and they're o.k. I've replaced the battery with a newly charged one, still no luck. Has anyone heard of this or any ideas? I've done a search on the net and can't find any info.