This question has come up and been answered on usenet.

groups.google.com

Here's one of the posts.

I've had this problem myself recently and I traced it down to the fact that I didn't have the locales I was requesting setup. I'm a debian user, so I'm not sure if this is the same as RedHat, but the default install only sets up the en_US locale, which is stored in /usr/lib/locale.

To get the others setup, I had to edit a configuration file /etc/locale.gen and uncomment all of the locales that I required.

I then had to run locale-gen (as root), this generates the required locales. After this the locales all worked fine, for everything.

Note that this setups the locales using the strict xx_XX language codes, so if you want french - french ( as apposed to canadian french fr_CA) you have to specify fr_FR. Likewise there is no "en" on it's own, if you want these two letter versions you'll have to add an entry in /etc/locale.alias.