How to enable a block cipher or hash algorithm for a keypair?

[Alphax]

Crest da Zoltral wrote:
> I searched any documentation i found on the net about how to edit keys,
> but I didn't found a way to enable a different cipher or digest? With
> `gpg --edit-key $key_id showpref` it's only possible to view the
> preferences and `gpg --edit-key $key_id pref` seems only to print the
> prefs in shorter harder to read form. So how can I enable Twofish and
> SHA-512 (without overriding the preferences with --cipher-algo and
> --digest-algo)?

$ gpg --edit-key 0xDEADBEEF
Secret key is available

pub  2048R/0xDEADBEEF  created: 2006-01-01  expires: never     usage: SC
                       trust: ultimate      validity: ultimate
sub  2048g/0xCAFEBABE  created: 2006-01-01  expires: never     usage: E
[ultimate] (1). Person (comment) <person at example.com>

Command> setpref h8 h10 h3 h2 s4 s9 s10 s8 s7 z3 z2 z1 mdc no-ks-modify
Set preference list to:
     Cipher: BLOWFISH, AES256, TWOFISH, AES192, AES, 3DES
     Digest: SHA256, SHA512, RIPEMD160, SHA1
     Compression: BZIP2, ZLIB, ZIP, Uncompressed
     Features: MDC, Keyserver no-modify
Really update the preferences? (y/N)

You need a passphrase to unlock the secret key for
user: "Person (comment) <person at example.com>"
2048-bit RSA key, ID 0xDEADBEEF, created 2006-01-01

Enter passphrase:

Command> quit
Save changes? (y/N) y

HTH,
-- 
                Alphax
        Death to all fanatics!
  Down with categorical imperative!
OpenPGP key: http://tinyurl.com/lvq4g

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