I’ve been dabbling with internationalizing my Swing-based programs, but for lack of a better explanation, all I ever get are placeholder boxes where the characters are supposed to be. How do I resolve this?
Not all fonts support these characters, try Arial and see whether that works.
You might be better off using logical fonts, which are mapped to more than one physical font for this sort of thing.
http://java.sun.com/javase/technologies/core/basic/intl/faq.jsp#desktop-rendering