On 4 March 2013, Senator Kate Lundy opened the NKRYPT sculpture. On the same day, Senator Lundy tweeted an encrypted tweet which I believe to be Unsolved.
Cipher Text of Tweet
Stuart K writes "the [NKRYPT] piece was developed before we had her or the idea of a coded tweet in mind… and we did want to suggest that if folk wanted to they could select their own coding protocol and use it… perhaps thinking about how a person might select a protocol based on a specifically personal 'attribute' might help with HER tweet"
Decrypted Text of Tweet