I've installed an hypervisor and an hypervisor with pae support. Both
configurations uses the same modules but only the kernel with pae
support boot. Why?
/boot/grub/menu.lst
title Xen 3.0.3-1-i386 / Debian GNU/Linux, kernel
[...]
module /vmlinuz-2.6.18-5-xen-686 root=/dev/md1 ro xencons=off
title Xen 3.0.3-1-i386-pae / Debian GNU/Linux, kernel
[...]
module /vmlinuz-2.6.18-5-xen-686 root=/dev/md1 ro xencons=off
You are booting the same kernel, which has PAE support, and which will
only work with PAE hypervisor.
If you want to run non PAE hypervisor, you have to run a kernel built
without PAE support.
Mehdi