Bug#390038: Bug#395359: Post-removal script fails on purge of linux-image-2.6.17-2-amd64

[Cesare Leonardi <celeonar@tiscali.it>]

I think that this bug can be merged with #390038 and #388696: they are 
about the same issue.

And to add information to these bug reports, i have verified that also 
the 2.6.18 series has the same problem (tryed to purge 
linux-image-2.6.18-1-486 version 2.6.18-3):

-----------------
(Reading database ... 100992 files and directories currently installed.)
Removing linux-image-2.6.18-1-486 ...
Running postrm hook script /sbin/update-grub.
Searching for GRUB installation directory ... found: /boot/grub
Testing for an existing GRUB menu.lst file ... found: /boot/grub/menu.lst
Searching for splash image ... none found, skipping ...
Found kernel: /boot/vmlinuz-2.6.18-1-686
Found kernel: /boot/vmlinuz-2.6.16-2-686
Updating /boot/grub/menu.lst ... done

The link /vmlinuz is a damaged link
Removing symbolic link vmlinuz
Unless you used the optional flag in lilo,
 you may need to re-run your boot loader[lilo]
The link /initrd.img is a damaged link
Removing symbolic link initrd.img
Unless you used the optional flag in lilo,
 you may need to re-run your boot loader[lilo]
Purging configuration files for linux-image-2.6.18-1-486 ...
Running postrm hook script /sbin/update-grub.
Searching for GRUB installation directory ... found: /boot/grub
Testing for an existing GRUB menu.lst file ... found: /boot/grub/menu.lst
Searching for splash image ... none found, skipping ...
Found kernel: /boot/vmlinuz-2.6.18-1-686
Found kernel: /boot/vmlinuz-2.6.16-2-686
Updating /boot/grub/menu.lst ... done

dpkg: error processing linux-image-2.6.18-1-486 (--purge):
 subprocess post-removal script returned error exit status 128
Errors were encountered while processing:
 linux-image-2.6.18-1-486
E: Sub-process /usr/bin/dpkg returned an error code (1)
A package failed to install.  Trying to recover:
-----------------

Regards.

Cesare.