$ sudo dpkg -i ../linux-2.6.27-rc6_8.g98df367_amd64.deb
(Reading database ... 164011 files and directories currently installed.)
Unpacking linux-2.6.27-rc6 (from .../linux-2.6.27-rc6_8.g98df367_amd64.deb) ...
dpkg: error processing ../linux-2.6.27-rc6_8.g98df367_amd64.deb (--install):
 trying to overwrite `/lib/firmware/kaweth/new_code.bin', which is also in package linux-2.6.27-rc5
dpkg-deb: subprocess paste killed by signal (Broken pipe)
arguments: 2.6.27-rc6 abort-install
Searching for GRUB installation directory ... found: /boot/grub
Searching for default file ... found: /boot/grub/default
Testing for an existing GRUB menu.lst file ... found: /boot/grub/menu.lst
Searching for splash image ... none found, skipping ...
Found kernel: /vmlinuz-2.6.27-rc5
Found kernel: /vmlinuz-2.6.27-rc4
Found kernel: /vmlinuz-2.6.26.3
Found kernel: /vmlinuz-2.6.26-1-amd64
Found kernel: /vmlinuz-2.6.25-2-amd64
Found kernel: /vmlinuz-2.6.18-4-amd64
Updating /boot/grub/menu.lst ... done

Errors were encountered while processing:
 ../linux-2.6.27-rc6_8.g98df367_amd64.deb

$ sudo dpkg -i --force-overwrite ../linux-2.6.27-rc6_8.g98df367_amd64.deb
(Reading database ... 164011 files and directories currently installed.)
Unpacking linux-2.6.27-rc6 (from .../linux-2.6.27-rc6_8.g98df367_amd64.deb) ...
dpkg - warning, overriding problem because --force enabled:
 trying to overwrite `/lib/firmware/kaweth/new_code.bin', which is also in package linux-2.6.27-rc5
dpkg - warning, overriding problem because --force enabled:
 trying to overwrite `/lib/firmware/kaweth/trigger_code.bin', which is also in package linux-2.6.27-rc5
dpkg - warning, overriding problem because --force enabled:
 trying to overwrite `/lib/firmware/kaweth/new_code_fix.bin', which is also in package linux-2.6.27-rc5
dpkg - warning, overriding problem because --force enabled:
 trying to overwrite `/lib/firmware/kaweth/trigger_code_fix.bin', which is also in package linux-2.6.27-rc5
Setting up linux-2.6.27-rc6 (8.g98df367) ...
arguments: 2.6.27-rc6 configure
update-initramfs: Generating /boot/initrd.img-2.6.27-rc6
Searching for GRUB installation directory ... found: /boot/grub
Searching for default file ... found: /boot/grub/default
Testing for an existing GRUB menu.lst file ... found: /boot/grub/menu.lst
Searching for splash image ... none found, skipping ...
Found kernel: /vmlinuz-2.6.27-rc6
Found kernel: /vmlinuz-2.6.27-rc5
Found kernel: /vmlinuz-2.6.27-rc4
Found kernel: /vmlinuz-2.6.26.3
Found kernel: /vmlinuz-2.6.26-1-amd64
Found kernel: /vmlinuz-2.6.25-2-amd64
Found kernel: /vmlinuz-2.6.18-4-amd64
Updating /boot/grub/menu.lst ... done