I got the same problem after install 3.12

uname -a
Linux overkill 3.12.0-031200-generic #201311071835 SMP Thu Nov 7 23:36:07 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

Building initial module for 3.12.0-031200-generic
configure: error:
*** Please make sure the kmod spl devel <kernel> package for your
*** distribution is installed then try again. If that fails you
*** can specify the location of the spl objects with the
*** '--with-spl-obj=PATH' option.
ERROR (dkms apport): kernel package linux-headers-3.12.0-031200-generic is not supported
Error! Bad return status for module build on kernel: 3.12.0-031200-generic (x86_64)
Consult /var/lib/dkms/zfs/0.6.2/build/make.log for more information.

more /var/lib/dkms/zfs/0.6.2/build/make.log
DKMS make.log for zfs-0.6.2 for kernel 3.12.0-031200-generic (x86_64)
Tue Nov 12 12:10:13 CET 2013
make: *** No targets specified and no makefile found. Stop.


I've downloaded and installed those packages from ubuntu kernel:
linux-headers-3.12.0-031200_3.12.0-031200.201311071835_all.deb
linux-headers-3.12.0-031200-generic_3.12.0-031200.201311071835_amd64.deb
linux-image-3.12.0-031200-generic_3.12.0-031200.201311071835_amd64.deb

It does work with 3.11.* ...