The Japanese forums are currently set to use iso-2022-jp (aka jis)
<meta content="text/html; charset=iso-2022-jp" http-equiv=Content-Type />
which would be great except that you're likely to get your text mangled by the forum code.
Covered in more detail in
Use of "charset=iso-8859-1" tag in _Japan_ Forum | Japan Forum
Actually "Don't use" is a bit of an exaggeration. "Don't enter Japanese text in iso-2022-jp (JIS)" is closer. You can post using the Quick Reply in other encodings (right click select Encoding->Japanese (Shift-JIS) or Japanese (EUC) or even Western European*). In some browsers (not IE) you can select encoding in Edit or normal Quote / Post windows.
* Sounds stupid - but actually works well on Windows XP + IE, or Windows XP + Firefox.
<meta content="text/html; charset=iso-2022-jp" http-equiv=Content-Type />
which would be great except that you're likely to get your text mangled by the forum code.
Covered in more detail in
Use of "charset=iso-8859-1" tag in _Japan_ Forum | Japan Forum
Actually "Don't use" is a bit of an exaggeration. "Don't enter Japanese text in iso-2022-jp (JIS)" is closer. You can post using the Quick Reply in other encodings (right click select Encoding->Japanese (Shift-JIS) or Japanese (EUC) or even Western European*). In some browsers (not IE) you can select encoding in Edit or normal Quote / Post windows.
* Sounds stupid - but actually works well on Windows XP + IE, or Windows XP + Firefox.