That's exactly the same error that Bonaojn was having.

FWIW, I did have her use the Millhouse scripts (nupgrade.sh) and the clone all seemed to go well (as evidenced by able to boot if external SD card is removed). This flasher error came after copying over a bootmenu.conf file to fix the N810 MMC naming bug and then needing to rerun the initfs_flasher.

So @ Bonaojn - so sorry that you're still having troubles but hopefully it was just something wrong with the flasher download.

I would suggest trying the following again from Pronuke's instructions (although I've made a addition shown in red):

Download the flasher application from here and save to "Documents"

http://fanoush.wz.cz/maemo/initfs_flasher.tgz
Install the flasher application to create a boot menu

# cd /home/user/MyDocs/.documents/
# tar zxvf initfs_flasher.tgz (check location of Tar first)
# cp path/to/your/bootmenu.conf /home/user/initfs_flasher/
# cd initfs_flasher/
# ./initfs_flash

Where the path to the bootmenu.conf would be something like "/media/mmc1/bootmenu.conf " if you just put it in the root directory of your external SD card. The internal SD card is /media/mmc2/

Hope this gets ya going