seamless ubuntu dual screen

[milkybarkid]

This is a brilliant product and it *almost* meets exactly my needs. The one thing that I can't make work is seamless mode across both of my monitors; here's what happens:
1) start the ubuntu VM (from xp host) up
2) allow guest auto resize
3) stretch the window across both monitors

so far, everything's great. I can launch linux apps and drag them anywhere I like on either monitor, but I can't access the windows desktop. So,

4) Enter seamless mode

Now it fails, linux now can't see the right hand monitor and the applications that were on the right hand monitor are now dumped back across onto the left hand one and I can no longer drag them back across.

What went wrong ?
I know that:

* Seamless mode does work on one monitor, so I think the guest additions 3.2.10 r66523) are ok
* I have no problems with sound/keyboard/mouse/share folders
* I have assigned 512MB as base memory and 64MB video memory
* Both 2D &3D accelerations are off and monitorcount is 1 (so http://www.virtualbox.org/manual/ch13.html "Guest multi-monitor support" limitation shouldn't apply)
* I have not used xorg.config
* Physical video card is nvidia quadro NVS 285 (standard mode) - I understand the linux can't see that directly

I've attached the log from a test run. Any help/suggestions would be enormously appreciated.

Thanks

[Sasquatch]

Seamless mode does work on one monitor

And that is exactly what is happening. It responds like any application that you maximize: it won't go beyond one physical display. If you want to have seamless with both monitors, then set the monitor count to 2. This will start two instances of the VB GUI for the VM, one for each monitor. When you go to seamless, both displays should do that, exactly what you want.