utf-8 not rendering properly

[Konstantin Svist]

I was looking stuff up on Wikipedia and noticed that some languages
didn't render properly.
Specifically, text in Khmer doesn't seem to be supported.
(see http://en.wikipedia.org/wiki/Cambodian_language or
http://km.wikipedia.org)

I was under the impression that utf-8 supported all languages...
Is this normal or is something screwy on my system?

BTW, using Fedora 8 (planning to jump to 11 once it comes out)