No, that's a mystery. And I have LANG=da.
And have no problems using foreign types.
Google .. Greek localization fedora ..
http://fedoraproject.org/wiki/L10N/Teams/Greek
http://fedoraproject.gr/
ls 230*
230φιλοξενούνται.mpg
totem =
totem-nautilus.i686 0:2.28.5-1.fc12
As you can see from the images, they all have Greek titles.
May be check the environment with the command : env
Fedora 12 shows LANG=da_DK.UTF-8 ..
Possible info : Please Google .. el_GR.UTF-8 ..
Could your settings be like el_GR ISO-8859-7 ?
.....