sheevaplug boot from nandfs hangs

[Ronald Klop]

Hello,

I succeeded in installing and booting my kernel (SHEEVAPLUG 10-current  
 from 22 nov.) from nandfs. I followed all the advise at  
http://wiki.freebsd.org/NAND. But the rootfs will not mount/start.

The end of the bootinfo is this:
cryptosoft0: <software crypto>
Timecounters tick every 1.000 msec
ipfw2 initialized, divert loadable, nat loadable, default to accept,  
logging disabled
usbus0: 480Mbps High Speed USB v2.0
ugen0.1: <Marvell> at usbus0
uhub0: <Marvell EHCI root HUB, class 9/0, rev 2.00/1.00, addr 1> on usbus0
uhub0: 1 port with 1 removable, self powered
Root mount waiting for: usbus0
ugen0.2: <USB 2.0> at usbus0
umass0: <USB 2.0 USB Flash Drive, class 0/0, rev 2.00/11.00, addr 2> on  
usbus0
umass0:  SCSI over Bulk-Only; quirks = 0x4000
umass0:0:0:-1: Attached to scbus0
Trying to mount root from nandfs:/dev/gnand0s.root []...
WARNING: NANDFS is considered to be a highly experimental feature in  
FreeBSD.
(probe0:umass-sim0:0:0:0): INQUIRY. CDB: 12 0 0 0 24 0
(probe0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
(probe0:umass-sim0:0:0:0): Retrying command
da0 at umass-sim0 bus 0 scbus0 target 0 lun 0
da0: <USB 2.0 USB Flash Drive 1100> Removable Direct Access SCSI-0 device
da0: 40.000MB/s transfers
da0: 3894MB (7975296 512 byte sectors: 255H 63S/T 496C)

The kernel is responsive because if I remove or insert the usb stick it  
displays messages about it. (Not shown above)
I'm connected via serial. What could be wrong? What information can I give  
more?
I installed /dev/gnand0s.root by tarring the content of / on my usb stick  
to the mounted /dev/gnand0s.root. That looked ok.

Regards,
Ronald.