"gpg: signing failed: Invalid length" when use brainpool512r1 keys to sign things

lid length Key generation failed: Invalid length Best regards, Yanzhe Lee 0x3EA647C79FDA9CD1.asc Description: application/pgp-keys signature.asc Description: OpenPGP digital signature ___ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.g

Cannot choose specific signing key with option --default-key

GPG Version: gpg (GnuPG) 2.1.21 libgcrypt 1.7.6 Operate System: macOS sierra 10.12.5 I have these keys with private key pub brainpoolP512r1/3EA647C79FDA9CD1 created: 2017-01-08 expires: 2032-01-05 usage: SCA trust: ultimate validity: ultimate ssb brainpoolP512r1/2D8801CE07BCC5B5 created: 2017-01