External Hard Drive Enclosure That Puts The Hard Drive To Sleep?

[Farani]

I bought an external hard drive enclosure for a Segate Barracuda 7200rpm drive I used to have in my alienware pc a while back. However, this enclosure will not put the drive to sleep after an hour like my Maxtor USB drive. These drives are all airdisks by the way. If I shut off the power switch on the drive, when I turn it back on, the airdisk doesn't recognize it and I have to unplug the airport. So, I need an enclosure that will power the drive down after a period of inactivity. Anybody have any enclosures they can suggest? I can't find anything online. Thanks!