Boot from hammer partition using vkernel

[Aleksej Lebedev]

Hi, everyone!

I wander what options do I specify if I want to run vkernel that boots 
from a hammer partition?
By default it boots from ufs:vkd0s0a, so I'm trying to pass 
vfs.root.mountfrom=hammer:vkd0s0a using option -e,
but colon is understood by vkernel as a delimiter for variable names.

So when I run
/var/vkernel/4.4/boot/kernel/kernel -m 2g -r /vhost/001.img -I 
/var/run/vknet -d -p /home/a/tmp/vhost001.pid -i 
/home/a/tmp/vhost001.memimg -e vfs.root.mountfrom=hammer:vkd0s0a

I get "Mounting root from hammer" message during the boot, which is 
understandable.
I tried to add backslash before the colon, but it didn't help.

In there a way to have a colon in the kernel variable value? Or maybe 
there is another way to boot from a hammer partition?

-- 
Aleksej Lebedev