The system tries to install xz utils, but does not progresses after: Unpacking replacement xz-utils ...

Binary package hint: xz-utils

$uname -a
Linux ???? 2.6.32-25-generic #45-Ubuntu SMP Sat Oct 16 19:48:22 UTC 2010 i686 GNU/Linux

$apt-cache policy xz-utils
xz-utils:
  Installed: 4.999.9beta+20091116-1
  Candidate: 4.999.9beta+20091116-1
  Version table:
     4.999.9beta+20091116-1 0
        500 http://us.archive.ubuntu.com/ubuntu/ lucid/main Packages
 *** 4.999.9beta+20091116-1 0
        100 /var/lib/dpkg/status

ProblemType: Package
DistroRelease: Ubuntu 10.04
Package: xz-utils 4.999.9beta+20091116-1
ProcVersionSignature: Ubuntu 2.6.32-25.45-generic 2.6.32.21+drm33.7
Uname: Linux 2.6.32-25-generic i686
AptOrdering: xz-utils: Remove
Architecture: i386
Date: Sun Oct 31 16:06:49 2010
Dependencies:

ErrorMessage: Package is in a very bad inconsistent state - you should reinstall it before attempting a removal.
InstallationMedia: Ubuntu 10.04.1 LTS "Lucid Lynx" - Release i386 (20100816.1)
PackageArchitecture: unknown
SourcePackage: xz-utils
Title: package xz-utils 4.999.9beta+20091116-1 failed to install/upgrade: Package is in a very bad inconsistent state - you should reinstall it before attempting a removal.