With a default Ubuntu 10.04 on VPS.net I have found that when running perl scripts the following warning is shown.
perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LANGUAGE = (unset), LC_ALL = (unset), LANG = "en_GB.utf8" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C").
After a bit of Googling I found the simple solution to be to do
sudo apt-get install language-pack-en
also I would recommend doing
sudo update-locale
which solves another locale issue.