[CentOS] copying data to CF card

  Hi all,

under centos 5 x86_64 - I was able to run fdisk to partition a CF card,
make the filesystem, copy data to the filesystem, run grub from an 
x86_64 system
to make the CF card bootable with grub. That all worked fine.

Now since switching to centos 6 x86_64 I run the exact same script
to program the CF card and when I insert that CF card into the end device
I get a Grub error 2.

I thought maybe a bad CF card... I tried 4 more times with 4 different 
CF cards.
Same result Grub error 2.

I then thought to try going back to centos 5 and try it with one of the 
4 CF cards
that did not work. It works under centos 5.

What might be happening here????

I can use fdisk after the script and see the partitions, I can mount the 
partition
all files are there, Running grub gives no errors. Just at boot I get 
"error 2".

Thanks,

Jerry