Thanks, you've got a point, but still I had no success.
Meanwhile, I have discovered that dmesg contains some useful(?) information on the error:
Some googling suggests that I may got the volume name wrong, I will look into that.

Update: I figured it out!
The missing step was an before mounting.

I am trying to put ubifs on the nand, currently to no avail. Here is what I got:

• I formatted mtd2 as a clean ubifs.
  ubiformat /dev/mtd2
• I attached mtd2 as ubi0:
  ubiattach /dev/ubi_ctrl -m 2
  UBI device number 0, total 4041 LEBs (521385984 bytes, 497.2 MiB), available 3997 LEBs (515708928 bytes, 491.8 MiB), LEB size 129024 bytes (126.0 KiB)
• Tried to mount the result:
  mount -t ubifs ubi2:root /mnt/ubi
  mount: ismeretlen fájlrendszertípus: "ubifs"
  (unknown filesystem type: "ubifs")
• checked /proc/filesystems:
  cat /proc/filesystems |grep ubi
  nodev   ubifs
  

Does anyone have a suggestion what I did wrong?
I am using the 2.6.32.4 kernel and debian lenny, except for the mtd-utils package, which is from squeeze and has version 20090606-1.

Thanks for the recommendation, now loading the kernel into memory works. However, the bootm 0x02000000 0x01100000  command does have difficulties:
(And it reboots after that...) It seems that the problem is with the initrd, as the kernel boots if I only specify bootm 0x02000000. This is all right for me, as I do not use an encrypted or remote root file system currently.
However, I may want to do that later, so if anyone has experience with debian initrd creation on the sheeva plug, please don't hold yourself back to share it with me.

sheeva.with-linux.com


Well, that is okay if your boot process does not hang...

I tried tried to use this kernel image, to no avail. If I type the following in uboot prompt:
I simply hangs there, I can't run the bootm command, I have to hard reset.
Does anyone have any idea what the problem could be?
Maybe the kernel is too big, and overwrites something (the uboot itself, maybe)?
Did anyone have a similar problem?

Ps: I generated the initrd with debian's standard tools, but even without loading it, the ex2load for the uimage hangs. However, it loads fine with the old kernel (kirkwood's 2.6.30-2).
Ps2: U-Boot 1.1.4 (Sep 14 2009 - 15:36:37) Marvell version: 3.4.19

My problem was that although /dev/ttyUSB0 appears, /dev/ttyUSB1 does not appear, and I can't connect to /dev/ttyUSB0 with any terminal program.
It does not matter if I let udev do the module loading or I load ftdi_sio manually.


I've read the above document, and it gave a tip about removing the brltty package, which I did.
After that, there was still no /dev/ttyUSB1, but I could connect to /dev/ttyUSB0 with gtkterm. Hoorray!

Someone should put this info into the wiki, as it is really useful for ubuntu users...