package libqt4-dbg (not installed) failed to install/upgrade:

[Mip Mipendorf]

Tried the upgrade from 9.10 to 10.04.

ProblemType: Package
DistroRelease: Ubuntu 10.04
Package: libqt4-dbg (not installed)
ProcVersionSignature: Ubuntu 2.6.31-20.58-generic
Uname: Linux 2.6.31-20-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Sun Apr 25 19:54:10 2010
ErrorMessage:
 ErrorMessage: no package named `libqt4-dbg' is installed, cannot configure
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
SourcePackage: qt4-x11
Title: package libqt4-dbg (not installed) failed to install/upgrade:

[Felix Geyer (debfx)]

Thank you for taking the time to report this bug and helping to make
Ubuntu better. It seems that there was an error on your system when
trying to install a particular package. Please execute the following
command, as it will clear your package cache, in a terminal:

sudo apt-get clean

Then try performing the update again. This will likely resolve your
issue, but the failure can be caused by filesystem or memory corruption.
So please also run a fsck on your filesystem(s) and a memory test. If
this does resolve your bug please set its status to Invalid. Thanks in
advance!

The relevent part of the log file:
Unpacking libqt4-dbg (from .../libqt4-dbg_4%3a4.6.2-0ubuntu5_amd64.deb) ...
d64.deb) ...
lzma: Decoder error
dpkg-deb: subprocess <decompress> returned error exit status 1
dpkg: error processing /var/cache/apt/archives/libqt4-dbg_4%3a4.6.2-0ubuntu5_amd64.deb (--unpack):
 short read in buffer_copy (backend dpkg-deb during `./usr/lib/debug/usr/lib/libQtGui.so.4.6.2')
No apport report written because the error message indicates a dpkg I/O error

[Mip Mipendorf (mbruell)]

Thanks for the help. The package in question must have become corrupted (probably in download - not sure), but clearing the cash, and reinstalling the package with a freshly downloaded one solved the issue. I marked the bug as invalid.

BTW - I've reported several bugs to Apple, and M$, but never Ubuntu. This was my first, and I did so really just to try to help the community. I didn't expect a reply (never got one from Apple or M$). Wow - thanks!! Anyway all is well. The new release seems pretty speedy too (and my hardware is about 5 years old now).