I had installed kali linux 1.05 64bits in my laptop. I've recently updated kali packages, and it seems I'v got now kali 1.06, but I'm still booting with kernel 3.7 .I've seen kernel 3.12 has already been installed with the rest of 1.06 updates, but I can't boot with it.
(in this same laptop I've got installed windows 8 and ubuntu 12.04 next to kali, and ubuntu rules the grub)

what should I do if I want to boot with kernel 3.12 instead of kernel 3.7?

Thanks for your help