I should have transitioned my old GPG key to a stronger one for long time, it’s finally done today, with the help of here and here. You can find my signed letter at http://ubuntuone.com/6O2OCf1rg9ulw1eWi13zc2. I am also copying the letter below for your convenience.

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256,SHA1

Due to rapid advancement of computing, my old 1024-bit DSA GPG key,
which was created 14 years ago in 1999, has long been deemed insecure.
Therefore, I am transitioning to a much stronger 8192-bit RSA key, by
using a slightly modified gnupg in [1], as the default gnupg does
not allow creation of keys greater than 4096-bit. Hopefully this new
key can survive much longer.

The old key will continue to be valid for some time, but I prefer all
future correspondence to come to the new one. I would also like this
new key to be re-integrated into the web of trust.  This message is
signed by both keys to certify the transition.

If you have signed my old key, I would appreciate signatures on my new
key as well, provided that your signing policy permits that without
reauthenticating me.

The old key, which I am transitioning away from, is:

pub   1024D/7BD22F74 1999-09-12
      Key fingerprint = CD09 4F7B BBEE 93CD 7966  6299 34B3 A9A0 7BD2 2F74
uid          Anthony Y. P. Wong (Personal) <ypwong@ypwong.org>

And the new key is:

pub   8192R/D28DA8DC 2013-06-01
      Key fingerprint = 8DF0 9030 F103 F760 C18C  BA06 605A A53D D28D A8DC
uid          Anthony Y. P. Wong (黃彥邦) <ypwong@ypwong.org>

To fetch the new key from a public key server using GnuPG, run:

  gpg --keyserver pgp.mit.edu --recv-key D28DA8DC

If you have already validated my old key, you can then validate that the
new key is signed by my old key:

  gpg --check-sigs D28DA8DC

If you are satisfied that you've got the right key, and the UIDs match
what you expect, I'd appreciate if you would sign my new key.

A simple and safe way to do that is by using caff (shipped in
Debian/Ubuntu as part of the "signing-party" package) as follows:

  caff D28DA8DC

Alternatively, you can sign the key by using gpg and send it to me (if
you have a functional MTA configured on your system) or upload the
signatures to a public keyserver directly:

  gpg --sign-key D28DA8DC
  gpg --armor --export D28DA8DC | mail -s 'OpenPGP Signatures' \
    ypwong@ypwong.org
  gpg --keyserver pgp.mit.edu --send-key D28DA8DC

Please let me know if there is any trouble, and sorry for the
inconvenience.

[1] https://launchpad.net/~anthonywong/+archive/ppa

Thanks,
Anthony Wong

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