how to fix dpkg error about

[Mitchell Laks <mlaks@post.harvard.edu>]

I get errors when using apt-get that are not fatal but are annoying.

I made my own kernel a while ago and used the wrong syntax. I have already removed this old kernel but the error
messages keep hanging around.

dpkg-query: warning: parsing file '/var/lib/dpkg/available' near line 25351 pack
age 'linux-image-2.6.20':
 error in Version string 'custon.1.0': version number does not start with digit
/etc/cron.daily/man-db:
dpkg-query: warning: parsing file '/var/lib/dpkg/available' near line 25351 pack
age 'linux-image-2.6.20':
 error in Version string 'custon.1.0': version number does not start with digit


Should i simply edit that file /var/lib/dpkg/available 

and delete the lines

Package: linux-image-2.6.20
Priority: optional
Section: base
Installed-Size: 62588
Maintainer: Unknown Kernel Package Maintainer <unknown@unconfigured.in.etc.kernel-pkg.conf>
Architecture: amd64
Source: linux-source-2.6.20
Version: custon.1.0
Provides: linux-image, linux-image-2.6
Depends: coreutils (>= 5.2.1)
Pre-Depends: debconf (>= 0.2.17) | debconf-2.0
Suggests: lilo (>= 19.1) | grub, fdutils, linux-doc-2.6.20 | linux-source-2.6.20
Size: 16788016
Description: Linux kernel binary image for version 2.6.20
 This package contains the Linux kernel image for version
 2.6.20.
 .
 It also contains the corresponding System.map file, and the modules
 built by the packager.  It also contains scripts that try to ensure
 that the system is not left in a unbootable state after an update.
 .
 Kernel image packages are generally produced using kernel-package,
 and it is suggested that you install that package if you wish to
 create a custom kernel from the sources. Please look at kernel-img.conf(5),
 and /usr/share/doc/kernel-package/README.gz  from the package kernel-package
 for details on how to tailor the  installation of this or any other kernel
 image package


the package was already removed i think

Rashi:/home/mlaks# dpkg -l|grep linux-image
ii  linux-image-2.6-amd64                            3.0.0+39                          Linux for 64-bit PCs (dummy package)
ii  linux-image-2.6-amd64-generic                    2.6.18+6                          Linux 2.6 image on all x86-64 - transition package
ii  linux-image-2.6.32-3-amd64                       2.6.32-9                          Linux 2.6.32 for 64-bit PCs
ii  linux-image-2.6.32-5-amd64                       2.6.32-30                         Linux 2.6.32 for 64-bit PCs
ii  linux-image-2.6.39.4-meshul                      1                                 Linux kernel binary image for version 2.6.39.4-meshul
ii  linux-image-3.0.0-1-amd64                        3.0.0-3                           Linux 3.0.0 for 64-bit PCs
ii  linux-image-3.0.4-meshul                         1                                 Linux kernel binary image for version 3.0.4-meshul
ii  linux-image-amd64                                3.0.0+39                          Linux for 64-bit PCs (meta-package)
Rashi:/home/mlaks# 

thanks
MItchell Laks