For J2SE 1.4.1 as part of a selection of CJK NIO Charset support addtions
a pair of ISO-2022-CN charsets were added. These were
sun.nio.cs.ext.ISO2022-CN-CNS
and
sun.nio.cs.ext.ISO2022-CN-GB

However, in both cases the Charset classes don't provide a decoder
(native bytes -> Unicode chars). J2SE does provide an older (pre NIO)
converter ISO-2022-CN which will recognize the encoded content and
will decode either ISO-2022-CN escaping scheme. However, since there
isn't yet a NIO coder which will perform such decoding it is best to
remove the ISO-2022-CN-* NIO coders for the time being until such
time that a full ISO-2022-CN NIO java Charset implementation is provided.

See bugID 4737614.