acting with with a generator implementation which,
   although it recognizes a given "x-" extension, uses it for a
   different purpose. All of the remaining extension namespace is
   reserved to IANA, which will only officially assign the extension

   into this namespace after the IESG approves of such an assignment.
   During the lifetime of the OTP WG, it is recommended that the IESG
   consult with the OTP WG prior to approving such an assignment.

3. The "hex" and "word" Responses

   There exists a v