I've found that a lot of upgrade commands and Apache on my system are failing with Segmentation faults. I don't know if this is the main one, but a lot of packages depend on util-linux:

root@myUbuntuHardyHeronServer:~# apt-get install util-linux
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be upgraded:
  util-linux
1 upgraded, 0 newly installed, 0 to remove and 72 not upgraded.
20 not fully installed or removed.
Need to get 0B/441kB of archives.
After this operation, 0B of additional disk space will be used.
(Reading database ... 20547 files and directories currently installed.)
Preparing to replace util-linux 2.13.1-5ubuntu2 (using .../util-linux_2.13.1-5ub
untu3.1_i386.deb) ...
Unpacking replacement util-linux ...
Segmentation fault
dpkg: warning - old post-removal script returned error exit status 139
dpkg - trying script from the new package instead ...
Segmentation fault
dpkg: error processing /var/cache/apt/archives/util-linux_2.13.1-5ubuntu3.1_i386
.deb (--unpack):
 subprocess new post-removal script returned error exit status 139
Segmentation fault
dpkg: error while cleaning up:
 subprocess post-removal script returned error exit status 139
Errors were encountered while processing:
 /var/cache/apt/archives/util-linux_2.13.1-5ubuntu3.1_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)