Changing the email address of a key

When I generated my new private key, I used one of my email addresses. This email address is stored both on the crypto stick and in the secring.gpg or pubring.gpg, probably both.
Now I would like to use that key with another email address. Is it possible to change the email address of a key, and how would I proceed to have it on the stick and in the gpg stub files?

I should report back here as well.
Peter and Werner from the gpg mailing list helped me solve this issue long ago.
Here is the answer:

My setup is more or less the following:
wiki.fsfe.org/Card_howtos/Card_w … ng_backups
with the addition of a sub key for ssh authentication:
programmierecke.net/howto/gpg-ssh.html -> section “with
smartcard (openpgp)”

The thing is that for a new UID, you need the, what they call, master key. That
would be the primary key. So when you followed the instructions under the
heading “Remove the master key from the keyring”, you where after that unable to
use your master/primary key to create a new UID.

So you go back a little in the document to the part where you had your USB stick
with the primary key and all subkeys guarded by Orcs or some other fearsome
creature. Plead with the creature to have your USB stick back, once again follow
the section “Go offline”, import your primary key from the USB stick (wipe away
the Orc spittle before inserting; ignore the chew marks on the protective cap).

After you have created the new UID with the primary key and exported the whole
to the USB stick, re-remove the primary key from the system.