tomsrtbt linux boot disk won't chroot - FATAL: kernel too old

I'm trying to build a Gentoo system (that won't boot the livecd) by using 
tomsrtbt.
Everything works great (I'm amazed how great tomsrtbt finds devices), 
until I get to the point where I need to chroot to /mnt/gentoo.
I get an error  FATAL: kernel too old

I'm running the latest version of the tomsrtbt boot disk, and it surprises 
me that I get this error -- since many people would need to chroot if 
they're using the boot disk to get to into another system.
Please help if you can.
Thanks,
Mike