I suggest add an option to allow writing ID3v2 in system code page.
This is not standard and therefore it's not going to be (re)added. You can use unicode for foreign characters. If your software or hardware player does not support unicode, try to contact the developers - we are in 2006. If web developers would take care of Netscape 4 compatibility, the web would not be where it is now.
Or just use ID3v1 in your national codepage. And ID3v2.4 in UTF-8 as the tag storage.