The Cessna 560 Citation N596VP c/n 560-0396 arrived in NZ from Australia and was registered ZK-AWK/2 on 20Nov2009. This did not last long, as the aircraft was cancelled on the 8th January as being sold abroad. It became N3937E while avionics work was carried out. The aircraft is seen here at Auckland International today, clearly marked as ZK-AWK, but this registration is not current on the CAA website.
No doubt all will become clear with time.
Presumably the ZK-AWK allocation has some significance. I cannot visualize any connection with the Tiger Moth topdresser ZK-AWK operated by Airspread Ltd., Mt Maunganui back in the 1950s!
(Acknowledgments to the MRC Aviation website for some of the details)