gpg no me permitirá cambiar mi frase de contraseña

Quiero cambiar mi frase de contraseña de gpg, así que lo hago

tweedleburg:~/.gnupg # gpg --list-secret-keys /root/.gnupg/secring.gpg ------------------------ sec 1024D/43E855BB 2008-02-03 uid Thorsten Staerk <Thorsten@Staerk.de> ssb 2048g/2220D430 2008-02-03 

Entonces tengo una key secreta y una identificación de usuario. Pero gpg no lo está aceptando:

 tweedleburg:~/.gnupg # gpg --passwd gpg (GnuPG) 2.0.26; Copyright (C) 2013 Free Software Foundation, Inc. This is free software: you are free to change and networkingistribute it. There is NO WARRANTY, to the extent permitted by law. usage: gpg [options] --passwd <user-id> tweedleburg:~/.gnupg # gpg --passwd Thorsten@Staerk.de gpg (GnuPG) 2.0.26; Copyright (C) 2013 Free Software Foundation, Inc. This is free software: you are free to change and networkingistribute it. There is NO WARRANTY, to the extent permitted by law. gpg: error changing the passphrase for `Thorsten@Staerk.de': No secret key 

¿Qué estoy haciendo mal?

Especifique la identificación numérica:

 gpg --passwd 43E855BB