Lubuntu 13.04 install fails, trying to install upstart-bin after upstart

I am trying to install lubuntu 13.10 on an IBM X40. (Installing 14.04 LTS gives a similar error, but the log file here is from 13.10.)
The process aborts while installing upstart-bin, complaining:

Dec 29 00:56:36 lubuntu ubiquity: dpkg: error processing /cdrom//pool/main/u/upstart/upstart-bin_1.13.2-0ubuntu2_i386.deb (--unpack):
Dec 29 00:56:36 lubuntu ubiquity: trying to overwrite '/etc/bash_completion.d/upstart', which is also in package upstart 1.13.2-0ubuntu2

A separate bug is that the install process identified this as an instance of bug #998492, which seems entirely unrelated. Should that be filed as a bug in apport?

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: upstart 1.10-0ubuntu7
ProcVersionSignature: Ubuntu 3.11.0-12.19-generic 3.11.3
Uname: Linux 3.11.0-12-generic i686
ApportVersion: 2.12.5-0ubuntu2
Architecture: i386
CasperVersion: 1.336ubuntu1
Date: Mon Dec 29 12:39:16 2014
LiveMediaBuild: Lubuntu 13.10 "Saucy Salamander" - Release i386 (20131016.1)
MarkForUpload: True
ProcKernelCmdline: initrd=/casper/initrd.lz file=/cdrom/preseed/username.seed boot=casper quiet splash -- BOOT_IMAGE=/casper/vmlinuz
SourcePackage: upstart
UpgradeStatus: No upgrade log present (probably fresh install)
UpstartBugCategory: System
UpstartRunningSessionVersion: init (upstart 1.10)
UpstartRunningSystemVersion: init (upstart 1.10)
modified.conffile..etc.init.hwclock.save.conf: [deleted]
modified.conffile..etc.init.tty1.conf: [modified]
modified.conffile..etc.init.tty2.conf: [modified]
modified.conffile..etc.init.tty3.conf: [modified]
modified.conffile..etc.init.tty4.conf: [modified]
modified.conffile..etc.init.tty5.conf: [modified]
modified.conffile..etc.init.tty6.conf: [modified]
mtime.conffile..etc.init.tty1.conf: 2014-12-29T11:32:51.035779
mtime.conffile..etc.init.tty2.conf: 2014-12-29T11:32:51.035779
mtime.conffile..etc.init.tty3.conf: 2014-12-29T11:32:51.039779
mtime.conffile..etc.init.tty4.conf: 2014-12-29T11:32:51.039779
mtime.conffile..etc.init.tty5.conf: 2014-12-29T11:32:51.039779
mtime.conffile..etc.init.tty6.conf: 2014-12-29T11:32:51.043779
upstart.upstart-file-bridge.log:
 Job got added /com/ubuntu/Upstart/jobs/unicast_2dlocal_2davahi
 Job got added /com/ubuntu/Upstart/jobs/update_2dnotifier_2dcrash
 Job got added /com/ubuntu/Upstart/jobs/update_2dnotifier_2drelease