ubiquity-dm crashed with ValueError in command(): invalid literal for int() with base 10: ''

[Fabio Marconi]

Hello
from usb+persistence.
At ubiquity-dm select to Try Ubuntu, system waste a lot of time to load the live session and this error popup.
Thanks
Fabio

ProblemType: Crash
DistroRelease: Ubuntu 12.10
Package: ubiquity 2.11.19
ProcVersionSignature: Ubuntu 3.5.0-8.8-generic 3.5.0
Uname: Linux 3.5.0-8-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.4-0ubuntu6
Architecture: amd64
CasperVersion: 1.320
Date: Thu Aug 9 15:44:31 2012
ExecutablePath: /usr/bin/ubiquity-dm
InstallCmdLine: noprompt cdrom-detect/try-usb=true persistent file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash -- maybe-ubiquity
InterpreterPath: /usr/bin/python3.2mu
LiveMediaBuild: Ubuntu 12.10 "Quantal Quetzal" - Alpha amd64 (20120809.1)
ProcCmdline: /usr/bin/python3 /usr/bin/ubiquity-dm vt7 :0 hostname /usr/bin/ubiquity --greeter --only
ProcEnviron:
 LANGUAGE=
 TERM=linux
 PATH=(custom, no user)
 LANG=
PythonArgs: ['/usr/bin/ubiquity-dm', 'vt7', ':0', 'hostname', '/usr/bin/ubiquity', '--greeter', '--only']
SourcePackage: ubiquity
Title: ubiquity-dm crashed with ValueError in command(): invalid literal for int() with base 10: ''
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1034981