problem formating disk with gpart

[Robert Huff]

	One of my systems has a hot-swap eSATA device, which reports as
"ad1".  I'm trying to use this to prepare a new disk using gpart and
something (possibly my understanding) is broken.
	After removing another disk and inserting the new one, I do:

>> gpart show ad1
=>       34  976773101  ad1  GPT  (465G)
         34  976773101       - free -  (465G)

	... which is the value for the disk just removed.
	If I do (to start clean):

>> gpart destroy ad1
gpart destroy ad1
gpart: Input/output error

	Huh?


					Robert Huff