fdisk (util-linux-2.9w-24.rpm) does need a blocksize option when used
on e.g. magneto-optical disks with 2048byte-sectors.
The manpage for fdisk does not mention -b option needed therefore,
which lead me to several hours of work in vain.
I know you can do it better!
This was fixed by 7.0; didn't check 6.2.