Changing preferences

[Kevin Hilton]

I think you are using the wrong command within your gpg.conf file


personal-cipher-preferences
personal-digest-preferences

These control what cipher/hash will be used when using other people's
public key.  showpref allows you as the sender to be aware of the
capabilities (ciphers/hashes) that are available on the recipients
machine.  You wouldn't want to send someone for example, a message
encrypted using the Camellia cipher, when the recipient would not have
capabilities by virtue of their gpg version to decrypt the message
because Camellia was not compiled into the executable.
personal-cipher-preferences (or digest) allows you as a sender to
choose algorithms that you prefer.  The firstmost algorithm contained
within your personal preference that is also within the key preference
list is chosen to encode or sign the message.

Preferences that are set at key generation time are controlled by the:
--default-preference-list string
    Set the list of default preferences to string. This preference
list is used for new keys and becomes the default for "setpref" in the
edit menu.

Hopefully that is clear.

-- 
Kevin Hilton