Kinematics for XYZAB mill

Hi guys, I am a bit lost on how to configure a kinematics module for a 5 AXIS XYZAB mill  something like this:
 
Any pointers or examples would be really appreciated as I'm not quite sure where to start modifying the provided linematics modules.

Hi,
i never set up a 5 axis mill with linuxcnc, but this kinematic is not right. B-axis usually wrapped around y-Axis- The C-Axis is wrapped around Z-axis. So the kinematic must be XYZAC and i think we have some examples here
linuxcnc.org/docs/html/motion/5-axis-kinematics.html

Should be the same thing as axis.sim.vismach.5axis.trt that is included with LinuxCNC, the difference being this has only one side on the rotating table while the sim has the table two sides hanging on bearings.
And that B there looks out of place, or A is out of place, depending on how you look at it.
The rotating part mounted on the swing arm should be C axis.
Edit:
After a bit of pondering and arguing, it is an AB machine.
Thank you Rod and JPL

I think the B axis is correct if it is assumed the swing arm is horizontal in its normal position. eg. it rotates between 6 clock and 12 oclock.  Its not XYZAC in that case. I nearly made that mistake.
And yes @chris, I've never set a 5 axis up either!

At 12 o'clock it will be inside the spindle, or the spindle will be inside the turnion/turn table, whatever is fastened better wins.

tommylight wrote:

At 12 o'clock it will be inside the spindle, or the spindle will be inside the turnion/turn table, whatever is fastened better wins.

I don't think such comments are useful.
What we need is  XYZAB kinematics no matter how foreign that sounds to you. 
Andy indicated its possible on this thread
forum.linuxcnc.org/10-advanced-configuration/41281-5-axis-xyzab
I need help in this area.