The Java Native Interface includes numerous functions that accept arguments of type char* or pointers to structs containing char* members. In most cases, the specification at http://java.sun.com/j2se/1.4.1/docs/guide/jni/spec/functions.doc.html does not specify the character encoding of these arguments. It should be clearly documented for each function and struct whether the char* arguments are encoded in the Java runtime's default encoding, in the Java-modified UTF-8 encoding specified at http://java.sun.com/j2se/1.4.1/docs/guide/jni/spec/types.doc.html#16542, in standard UTF-8, or in some other encoding.