Short answer: No
Long answer:
The "Virtualization inside a virtualizer" is called on several google result as "nested virtualization" if you search more reference.
From virtual box documentation(http://www.virtualbox.org/manual/ch02.html#idp12630656):
VirtualBox uses a special kernel module called vboxdrv to perform
physical memory allocation and to gain control of the processor for
guest system execution. Without this kernel module, you can still use
the VirtualBox manager to configure virtual machines, but they will
not start. In addition, there are the network kernel modules
vboxnetflt and vboxnetadp which are required for the more advanced
networking features of VirtualBox.
In order to use Virtualbox you need to load the vboxdrv, in a Virtuozzo container you can't modify any kernel configuration because the kernel is shared between all the container of the same physical machine.