We apply non-binary channel coding to the symmetric multi-carrier two-way relay channel and evaluate two decoding approaches at the relay. Complete-decode-and-forward (CDF) decodes the packets of both users before forwarding the binary sum in the second phase, while functional-decode-and-forward (FDF) directly decodes the binary sum of both packets. For both approaches, we study suitable power and rate allocation strategies and apply single-user and joint decoding of both packets.