problems virtualizing ubuntu server 16.04

[tech-lists]

Hi,

I prepare device.map and load grub the usual way:

grub-bhyve -m ./device.map -r cd0 -M 4096M ubtest1604

and get a screen up that says:

Install Ubuntu Server
Install MAAS Region Controller
Install MAAS Rack Controller
Check disc for defects
Rescue a broken system

I select the first one and get this error:

error: invalid magic number.
error: you need to load the kernel first.

Press any key to continue...
...and any key dumps me back to the same screen. I have to open another
term and kill the process in order to exit this screen.

For curiosity I tried all the others as well, same error.

What am I doing wrong? Is ubuntu 16.04 too new for bhyve?

freebsd host is 10.1-RELEASE #0 r275428
grub is grub2-bhyve-0.40
ports are at r419340

thanks,
-- 
J.