Comment 1 for bug 262783

I have experience this as well when attempting to install my custom compiled 2.6.28.x series kernel.

dpkg: error processing linux-image-2.6.28.7-em64t_1_amd64.deb (--install):
trying to overwrite `/lib/firmware/atmsar11.fw', which is also in package linux-image-2.6.27.10-em64t
dpkg-deb: subprocess paste killed by signal (Broken pipe)

Here is the complete log:

$ sudo dpkg -i linux-image-2.6.28.7-em64t_1_amd64.deb
[sudo] password for squishy:
(Reading database ... 144190 files and directories currently installed.)
Unpacking linux-image-2.6.28.7-em64t (from linux-image-2.6.28.7-em64t_1_amd64.deb) ...
Done.
dpkg: error processing linux-image-2.6.28.7-em64t_1_amd64.deb (--install):
 trying to overwrite `/lib/firmware/atmsar11.fw', which is also in package linux-image-2.6.27.10-em64t
dpkg-deb: subprocess paste killed by signal (Broken pipe)
Running postrm hook script /sbin/update-grub.
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: /boot/vmlinuz-2.6.27.10-em64t
Found kernel: /boot/vmlinuz-2.6.27-11-generic
Found kernel: /boot/memtest86+.bin
Updating /boot/grub/menu.lst ... done

Errors were encountered while processing:
 linux-image-2.6.28.7-em64t_1_amd64.deb