root@nemesis:~# apt-get upgrade  cpp debianutils fontconfig grep-dctrl initscripts libfontconfig1 libhtml-parser-perl sysvinit
Reading package lists... Done
Building dependency tree... Done
The following packages have been kept back:
  cpp debianutils fontconfig grep-dctrl initscripts libfontconfig1 libhtml-parser-perl sysvinit
The following packages will be upgraded:
  apt
1 upgraded, 0 newly installed, 0 to remove and 8 not upgraded.
1 not fully installed or removed.
Need to get 0B/1437kB of archives.
After unpacking 418kB of additional disk space will be used.
Do you want to continue [Y/n]?
WARNING: The following packages cannot be authenticated!
  apt
Install these packages without verification [y/N]? y
Setting up debian-archive-keyring (2007.02.19) ...
ERROR: Can't find the archive-keyring
Is the ubuntu-keyring package installed?
dpkg: error processing debian-archive-keyring (--configure):
 subprocess post-installation script returned error exit status 1
Errors were encountered while processing:
 debian-archive-keyring
E: Sub-process /usr/bin/dpkg returned an error code (1)
root@nemesis:~#