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

When start the install crashed..

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: ubiquity 2.7.10
ProcVersionSignature: Ubuntu 3.0-1.2-generic 3.0.0-rc3
Uname: Linux 3.0-1-generic i686
NonfreeKernelModules: wl
Architecture: i386
Date: Fri Jun 24 02:59:10 2011
ExecutablePath: /usr/bin/ubiquity-dm
InterpreterPath: /usr/bin/python2.7
ProcCmdline: /usr/bin/python /usr/bin/ubiquity-dm vt7 :0 hostname /usr/bin/ubiquity --only
ProcEnviron:
 LANGUAGE=
 PATH=(custom, no user)
 LANG=es_ES.UTF-8
PythonArgs: ['/usr/bin/ubiquity-dm', 'vt7', ':0', 'hostname', '/usr/bin/ubiquity', '--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: