The following chars are not defined in CharsetEncoder/Decoder
0xA4 0x20AC # EURO SIGN
0xA5 0x20AF # DRACHMA SIGN
0xAA 0x037A # GREEK YPOGEGRAMMENI
justification : http://www.unicode.org/Public/MAPPINGS/ISO8859/8859-7.TXT

also solaris defines :
0xAE EROTIMATIKO
as well as the above 3.
This web directory
http://www.unicode.org/Public/MAPPINGS/ISO8859/DatedVersions/
demonstrates that (according to the Unicode Consortium)
ISO-8859-7 is the *only* ISO-8859 standard that comes in multiple
dated revisions.

When only a few characters are being added, it is compatible enough
to simply add them to the existing charset implementation, rather
than being ultra-pedantic and creating a charset named ISO-8859-7:2003.