I can't see my characters, they are just white boxes... I'm running ubuntu (xubuntu) 9.04
I have some questions to ask:
1) What version are you using?
2) What is the graphics card (and what drivers are being used)?
The more info you can offer the more likely it is to solve the problem.
A debug log might be helpful too.
I'm guessing he's using a chinese or japanese localisation, alternate font was hacked into 0.9.11 - but prior was lil' white boxes due to unmatched chars.
Just a guess though.