You need to confirm that this actually fixes your problem. The problem I see described in the above links are related to crashdump (kexec/kdump interaction), which seems nothing like what you are describing. Also, the fix is in x86_64, which wont affect the -686 kernel image, nor would it fix a CoreDuo system.
Did you try booting with "noapic"? ** Changed in: linux-source-2.6.15 (Ubuntu) Status: Unconfirmed => Needs Info -- Kernel panic - not syncing: IO-APIC + timer doesn't work! https://launchpad.net/bugs/52553 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs