Custom encoder + entity id -> fails

[Crafter6432]

Hello,

I tried to use javas UUID as ID for my Entitys because the text UUIDs provided by Activate wasting to much space so i tried to encode javas UUID as binary. That works for all fields except the id.

Exeption:

https://gist.github.com/Crafter6432/0c60bdfc1363c35d3a0b

Encoder:
https://gist.github.com/Crafter6432/3c4f5de7c807d846024b

Models:

https://gist.github.com/Crafter6432/20da3c72083752a67cc9

Scala: 2.11.4
Activate: 1.7