Can't boot Angstrom from NAND

Hi all,
I *used* to have a working BB with Angstrom booting from NAND. For
reasons that are still unclear, this config has stopped working. I
used Koen's demo which boots from an SD Card, then installs Angstrom
in the BB;s NAND.

The main error is:
NAND read: device 0 offset 0x280000, size 0x400000
  4194304 bytes read: OK
Wrong Image Format for bootm command
ERROR: can't get kernel image!

What are some steps I can take to diagnose the problem?
Thanks in advance!

try to format the sd card according to this page :
it worked for me

You need to reload the kernel image on nand

mmc init
fatload mmc 0:1 80000000 uImage

nandecc sw
nand erase 280000 400000
nand write 80000000 280000 400000

make sure the uImage is in your sd card.