Custom Kernel Target Ignored

[Carolyn Longfoot]

When I start
cd /usr/src
make buildkernel KERNELCONF=MYKERNEL

then the process start and gives
--------------------------------------------------------------
>>> Kernel build for GENERIC started on Sat Feb 25 10:59:25 EST 2012
--------------------------------------------------------------
Even though my config file has
ident MYKERNEL

I checked and there are no rogue versions of MYKERNEL (like a straight copy from GENERIC) and it exists in
/usr/src/sys/amd64/conf

I'm probably missing something really simple here, why would 'make' go for GENERIC instead of my custom config?
This is 9.0 RELEASE.

Thanks,
Caro