The files will be in different character encodings
(e.g. perhaps GB or Big-5 for the Chinese, and
ISO-8859-7 for Greek) or in utf-8? Something else?
Take a look at the character encodings explanation on
the w3 site.
If they are in utf-8, you can read them with vi, etc.
in the more recent version of xterm windows (if properly
configured to point to the proper fonts, etc.)
If they are not in utf-8, or if you don't have the more
recent version of xterm, or just to give yourself more
options, I recommend that you install Yudit (www.yudit.org)
and use xconv, a tool that comes with it.
These will let you view characters in virtually any encoding
and help you convert between encodings on the fly.
Btw, some people say that php is not so utf-8 friendly.
Personally, I haven't found that to be the case (yet).
Good luck!
Tony Laszlo, Tokyo
http://www.issho.org/laszlo.html