FreeBSD 9.0-BETA2 invalid ada0 layout prevents installation

Hi,

Tried to install the BETA2 from a mem-stick onto a 250Gb disk.
Which turned out to be used in a ZFS box.
Since it does contain GPT info telling me ada0p1 was a freebsd-zfs partion.

This however results in that I can not find any "normal" way in the 
guided and expert config menus to actual tell it to use the whole disk 
for a new fresh FreeBSD install.

it keeps complaining
	Operation not permitted
	'ada0 table is corrupt'

Only way to proceeds seems to be is to go to shell, dd /dev/zero over 
the first few blocks and then restart....

Not shure that many people that end up using a ZFS old disk, also do not 
know how to fix this. But then again, what is there is another "corrupt" 
GPT setup on the disk...

--WjW