fedora 18 broken install :: you have not created a bootloader stage1 target device

[Adrian Sevcenco]

Hi! I try to install fedora 18 (fresh install not update) and after
custom partitioning (which was NOT obvious to choose) i receive this error :
"you have not created a bootloader stage1 target device
sda2 must have one of the following disklabel types :gpt."

the former / (sda2) i checked to be reformated ..

so .. what is going on ? f17 was happy on this thinkpad 420 ...
why not f18? Any ideea how can i skip this? (because i DO NOT WANT to
reformat my disk)

Thanks!
Adrian