Locale Issues Will Not Allow Application Launching

[yn2]

Hello,

Have a machine with Ubuntu 13.04 installed on it. No additional repos added. Has issues with Locale which have been problematic with perl but since i don't code in perl i ignored it until now. Trying to start bitcoind but getting a core dump.
The error is this:

user@machine:~/.bitcoin$ bitcoind
terminate called after throwing an instance of 'std::runtime_error'
what(): locale::facet::_S_create_c_locale name not valid
Aborted (core dumped)

When tried an unknown command getting this error:

user@machine:~/.bitcoin$ what
Sorry, command-not-found has crashed! Please file a bug report at:
https://bugs.launchpad.net/command-not-found/+filebug
Please include the following information with the report:

command-not-found version: 0.3
Python version: 3.3.1 final 0
Distributor ID: Ubuntu
Description: Ubuntu 13.04
Release: 13.04
Codename: raring
Exception information:

unsupported locale setting
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/CommandNotFound/util.py", line 24, in crash_guard
callback()
File "/usr/lib/command-not-found", line 69, in main
enable_i18n()
File "/usr/lib/command-not-found", line 40, in enable_i18n
locale.setlocale(locale.LC_ALL, '')
File "/usr/lib/python3.3/locale.py", line 541, in setlocale
return _setlocale(category, locale)
locale.Error: unsupported locale setting

Any ideas on what to do?
My locale is US:

user@machine:~/.bitcoin$ cat /etc/default/locale
LANG="en_US.UTF-8"

Thanks

[safir]

I have the same problem. I upgraded from Ubuntu 13.04 AMD64 to Ubuntu 13.10 AMD64 saucy. Upgrade went well but then on login get the same message. I am using AMD 64 processor. When I use /etc/default/locale, it says I don't have permission. LANG="en_US.UTF-8" doesnot allow to change locale.
Sorry, command-not-found has crashed! Please file a bug report at:
https://bugs.launchpad.net/command-not-found/+filebug
Please include the following information with the report:

command-not-found version: 0.3
Python version: 3.3.2 final 0
Distributor ID: Ubuntu
Description: Ubuntu 13.10
Release: 13.10
Codename: saucy
Exception information:

unsupported locale setting
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/CommandNotFound/util.py", line 24, in crash_guard
callback()
File "/usr/lib/command-not-found", line 69, in main
enable_i18n()
File "/usr/lib/command-not-found", line 40, in enable_i18n
locale.setlocale(locale.LC_ALL, '')
File "/usr/lib/python3.3/locale.py", line 541, in setlocale
return _setlocale(category, locale)
locale.Error: unsupported locale setting