Mac Pro 2010: Not Compatible with Some External HDs

Apple published a TechNote to announced that the new Mac Pro 2010 will lack compatibility with some controllers found usually in external HD enclosures Oxford OXUF934DSB. There are usually found in quad interface enclosures (eSATA, USB2.0, Firewire 400 and 8000.
According to Apple, such drives would randomly refuse to automatically mount when booting the Mac Pro Apple. To fix the problem, you will need to wait for couple of second after booting the Mac Pro before turning the external HD on. A solution will most probably be found soon, either via a firmware update of the controller, or a driver update.