package libpam-runtime 1.1.2-2ubuntu8 failed to install/upgrade: subprocess installed pre-removal script returned error exit status 1

[Nikhil Mani]

sudo apt-get upgrade

Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be upgraded:
  libpam-runtime
1 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 42.1 kB of archives.
After this operation, 0 B of additional disk space will be used.
Do you want to continue [Y/n]? y
Err http://in.archive.ubuntu.com/ubuntu/ natty-updates/main libpam-runtime all 1.1.2-2ubuntu8.2
  404 Not Found [IP: 91.189.88.30 80]
Err http://security.ubuntu.com/ubuntu/ natty-security/main libpam-runtime all 1.1.2-2ubuntu8.2
  404 Not Found [IP: 91.189.92.166 80]
Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/p/pam/libpam-runtime_1.1.2-2ubuntu8.2_all.deb 404 Not Found [IP: 91.189.92.166 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

ProblemType: Package
DistroRelease: Ubuntu 11.04
Package: libpam-runtime 1.1.2-2ubuntu8
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic i686
Architecture: i386
Date: Tue May 31 18:55:19 2011
ErrorMessage: subprocess installed pre-removal script returned error exit status 1
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release i386 (20110427.1)
PackageArchitecture: all
SourcePackage: pam
Title: package libpam-runtime 1.1.2-2ubuntu8 failed to install/upgrade: subprocess installed pre-removal script returned error exit status 1
UpgradeStatus: No upgrade log present (probably fresh install)

[bthelm2 (bthelm2)]

I too, am experiencing this.