ubiquity crashed with InstallStepError in configure_bootloader()

Binary package hint: ubiquity

I was trying to install Karmic to my USB-HDD. It happens when completing the installation(In the GRUB installing phase I think). It doesn't show any error message, setup window just disappeares. I tried 3 times, and they were all the same.

ProblemType: Crash
Architecture: amd64
Date: Sun Nov 1 17:20:56 2009
DistroRelease: Ubuntu 9.10
ExecutablePath: /usr/lib/ubiquity/bin/ubiquity
InterpreterPath: /usr/bin/python2.6
LiveMediaBuild: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
Package: ubiquity 2.0.6
ProcCmdline: /usr/bin/python /usr/lib/ubiquity/bin/ubiquity gtk_ui
ProcEnviron: Error: [Errno 13] Permission denied: '/proc/3716/environ'
ProcVersionSignature: Ubuntu 2.6.31-14.48-generic
PythonArgs: ['/usr/lib/ubiquity/bin/ubiquity', 'gtk_ui']
SourcePackage: ubiquity
Title: ubiquity crashed with InstallStepError in configure_bootloader()
Uname: Linux 2.6.31-14-generic x86_64
UserGroups:

XsessionErrors:
 (gnome-settings-daemon:3547): GLib-CRITICAL **: g_propagate_error: assertion `src != NULL' failed
 (gnome-settings-daemon:3547): GLib-CRITICAL **: g_propagate_error: assertion `src != NULL' failed
 (nautilus:3590): Eel-CRITICAL **: eel_preferences_get_boolean: assertion `preferences_is_initialized ()' failed
 (polkit-gnome-authentication-agent-1:3629): GLib-CRITICAL **: g_once_init_leave: assertion `initialization_value != 0' failed