ubiquity crashed with DebconfError in command(): (10, "debian-installer/fallbacklocale doesn't exist")

[Steven]

Binary package hint: ubiquity

Ubiquity won't start in today's daily build. Installing from a usb stick.

ProblemType: Crash
DistroRelease: Ubuntu 11.04
Package: ubiquity 2.5.26
ProcVersionSignature: Ubuntu 2.6.38-6.34-generic 2.6.38-rc7
Uname: Linux 2.6.38-6-generic i686
Architecture: i386
Date: Thu Mar 17 11:28:58 2011
ExecutablePath: /usr/lib/ubiquity/bin/ubiquity
InterpreterPath: /usr/bin/python2.7
LiveMediaBuild: Ubuntu 11.04 "Natty Narwhal" - Alpha i386 (20110316)
ProcCmdline: /usr/bin/python /usr/lib/ubiquity/bin/ubiquity gtk_ui
ProcEnviron: Error: [Errno 13] Permission denied: '/proc/3392/environ'
PythonArgs: ['/usr/lib/ubiquity/bin/ubiquity', 'gtk_ui']
SourcePackage: ubiquity
Title: ubiquity crashed with DebconfError in command(): (10, "debian-installer/fallbacklocale doesn't exist")
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make Ubuntu better. This particular crash has already been reported and is a duplicate of bug #445499, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.