Compiling

I want to copy my config from my exisiting kernel to xen I have a procedure but i believe it to be imperfect..can anyone help with this?

my existing kernel is 2.6.12-10-386

I copied config-2.6.12-10-386 from /boot to ~/xen/xen-unstable.hg/linux-2.6.16-rc5-xen0/.config

sudo make oldconfig ARCH=xen CC=gcc-3.3 HOSTCC=gcc-3.3

I do a    sudo make menuconfig ARCH=xen CC=gcc-3.3 HOSTCC=gcc-3.3           in the ~/xen/xen-unstable.hg/linux-2.6.16-rc5-xen0 directory