Transfer subkey to other keyring

[Jack Bates]

On 27/06/13 12:49 AM, Werner Koch wrote:
> On Wed, 26 Jun 2013 20:00, di44vq at nottheoilrig.com said:
>
>> Thanks Werner, I want to keep my primary key on a separate keyring
>> (does this require putting subkeys under a different primary key?)
>
> No.  We use a stub key instead.  The command is
>
>    gpg --export-secret-subkeys KEYID >newkey.gpg
>
> Run that command on a secure box.  On your everyday box make sure that
> the secret KEYID does not exist and then import newkey.gpg.

Thanks Werner, I think that is the command I am running (and that is 
giving me the error), except that I am using the key id of a subkey, 
with an exclamation mark, to export just one subkey instead of all the 
subkeys belonging to the primary key. The subkey with that key id 
definitely doesn't already exist in the destination keyring, although 
the destination keyring does already contain a different subkey. I tried 
to import the new subkey with and without "--import-options merge-only", 
but in both cases I get the same error:

    gpg: key 7FABB65F: already in secret keyring
    gpg: Total number processed: 1
    gpg:       secret keys read: 1
    gpg:  secret keys unchanged: 1