My next try :
Like, I believe Joerg_rw also found, is the 'secret mode' when pressing vol-up on power-on.
I believe this may be an entrance to a quick-recovery.

What I want to try (once I get around to buying a 16G SDcard)
This requires an unlocked bootloader.

insert 16Gb SD card
fastboot -i 0x2931 boot boot-telnet-initrd.img
telnet 192.168.42.17
dd if=/dev/mmcblk0 of=/dev/mmcblk1

power off
power-on - holding vol-up

And see if this will start a flash from SD card, now containing a proper partition layout, like the device.
Possibly, if it work, it is also doable to just create the partition layout on the SD card, and dd mmcblk0p17 to mmcblk1p17