Booting SmartOS 20120309T073819Z directly from iPXE (aac9718) gives error

error.txt

Download of kernel+initrd works on real hardware (HP/Compaq 6730b),
but this message comes up after a few seconds.

================================
krtld: failed to open 'unix'
krtld: bind_primary(): no relocation information found for module unix
krtld: error during initial load/link phase

krtld could neither locate nor resolve symbols for:
    unix
in the boot archive. Please verify that this file
matches what is found in the boot archive.
You may need to boot using the Solaris failsafe to fix this.
Unable to boot
Press any key to reboot.
=================================

On VirtualBox it just hangs after kernel+initrd download completes.

smartos.ipxe

#!ipxe
echo
echo Starting SmartOS for ${hostname}
set base-url http://server.smidsrod.lan/tftp/smartos/platform/i86pc
kernel ${base-url}/kernel/amd64/unix
initrd ${base-url}/amd64/boot_archive
imgargs unix -B console=text,standalone=true,noimport=true,root_shadow='long-line-of-encrypted-password'
boot || 
# If everything failed, give the user some options
echo Boot from ${base-url} failed
prompt --key 0x197e --timeout 2000 Press F12 to investigate || exit
shell