Certain TLS ALPN values couldn't be properly read or written by the SunJSSE provider. This is due to the choice of Strings as the API interface and the undocumented internal use of the UTF-8 Character Set which converts characters larger than U+00007F (7-bit ASCII) into multi-byte arrays that may not be expected by a peer.

ALPN values are now represented using the network byte representation expected by the peer, which should require no modification for standard 7-bit ASCII-based character Strings. However, SunJSSE now encodes/decodes String characters as 8-bit ISO_8859_1/LATIN-1 characters. This means applications that used characters above U+000007F that were previously encoded using UTF-8 may need to either be modified to perform the UTF-8 conversion, or set the Java security property *`jdk.tls.alpnCharset`* to "UTF-8" revert the behavior.