Load up a customized DSDT on Ubuntu 8.04.1

I got some pains in my original DSDT so that I decide to load up a customized version of DSDT.aml.
Here is what I have to do in my Ubuntu box.

1. Backup vmlinuz and initrd images under /boot (use root permission to keep owner/group):
$ sudo cp /boot/vmlinuz-$(uname -r) ~/vmlinuz-$(uname -r)
$ sudo cp /boot/initrd.img-$(uname -r) ~/initrd.img-$(uname -r)

2. Copy your DSDT.aml to proper dir and reconfigure your initrd image (case-sensitive):
$ sudo cp DSDT.aml /etc/initramfs-tools/DSDT.aml
$ sudo dpkg-reconfigure linux-image-$(uname -r)

3. Edit GRUB boot menu (depands on your demand, optional):
$ sudo vim /boot/grub/menu.lst
- Find out the booting kernel you want, and append a parameter "acpi=force" after the line starting with kernel.

4. Save it and reboot. Use "dmesg |more" to check if there is any error happened for new DSDT.