Just read this from the NOG list:
This message is to inform you that TelstraClear will be making changes to its recursive DNS service for broadband and dialup customers.
As part of TelstraClear's ongoing network improvements, we are deploying the following enhancements:
--- Current recursive DNS servers to be replaced by multiple geographically diverse DNS clusters;
--- Anycast routing to be implemented to direct traffic to the nearest DNS cluster;
--- Native IPv6 transport implemented for recursive DNS service;
--- Recursive DNS queries will only be accepted from TelstraClear broadband and dialup customers.
TelstraClear is currently allowing some non-TelstraClear New Zealand IP address blocks to access the following recursive DNS servers:
Once we have deployed the above enhancements, only queries from TelstraClear broadband and dialup customers will be accepted to the TelstraClear recursive DNS servers. If you are currently using the above name servers, and are on non-TelstraClear IP address space, you will need to change your DNS configuration to use alternative name servers.