Second SATA device lost after ZFS root is mount

hi,
I have laptop with two hard disks - SSD and HDD attached instead of optical
drive, running 9.0-PRERELEASE, GENERIC and custom configured kernel (same symptoms for both).
Second HDD is lost during boot (root is on ada0, ada0 and ada1 are partitioned using GPT):

ada1 at ahcich1 bus 0 scbus1 target 0 lun 0
ada1: <ST9500420AS 0003LVM1> ATA-8 SATA 2.x device
ada1: 300.000MB/s transfers (SATA 2.x, UDMA5, PIO 8192bytes)
ada1: Command Queueing enabled
ada1: 476940MB (976773168 512 byte sectors: 16H 63S/T 16383C)
ada1: Previously was known as ad6
....
Trying to mount root from zfs:zroot []...
(ada1:ahcich1:0:0:0): lost device
(ada1:ahcich1:0:0:0): removing device entry
cryptosoft0: <software crypto> on motherboard
GEOM_ELI: Device gpt/home0.eli created.

loader.conf contains only few modules:

# Kernel Options
kern.ipc.shmseg=1024
kern.ipc.shmmni=1024
kern.maxproc=10000

# Required by Firefox
sem_load="YES"
# ACPI drivers
acpi_load="YES"
acpi_video_load="YES"
acpi_ibm_load="YES"
acpi_dock_load="YES"
# Linuxulator
linux_load="YES"
# Linux specific pseudo-devices
lindev_load="YES"
# Bluetooth driver
ng_ubt_load="YES"
# Realtek driver
if_re_load="YES"
legal.intel_iwn.license_ack=1

# Virtualbox driver (kmod)
vboxdrv_load="YES"

# ZFS driver and settings
zfs_load="YES"

# open files
kern.maxfiles=49312
kern.maxfilesperproc=16384

# ZFS Root file system
vfs.root.mountfrom="zfs:zroot"

The same symptoms are for original DVD Drive - it is lost during the boot
when ZFS root is successfully mount and before GELI asks for password.
What is most strange it doesn't occur when boot into single user mode. 
What can be the cause?

-- 
Sebastian Chmielewski * jid:chmielsster_at_gmail.com * gg:3336919 * icq:224161389

-- 
Sebastian Chmielewski * jid:chmielsster_at_gmail.com * gg:3336919 * icq:224161389