[Nix-dev] Problem booting the new nixos kernel

[Marco Maggesi]

Hi,

I just updated nixos (nixos-rebuild switch) and I get the following  
error at
boot time:

   This kernel requires the following features not present on the CPU:
   pae
   Unable to boot - please use a kernel appropiate for your CPU.

I run nixos inside a VirtuabBox machine (on a MacBook Pro, Intel Core  
Duo,
if that matters).

What can I do?

Thank you,
M.