I'm off on a non-climbing trip to NZ, but going to pop my shoes in just in case. Was thinking of taking a wee bit of chalk in a plastic bag as well, but is this a bad idea in terms of getting through immigration etc?
In reply to Ali:
The kiwis are rightly worried about things coming into contaminate the ecosystem, but their main concern is over little critters and plants that can reproduce and take over the place. Given your chalk's inability to reproduce, a small bag can't have a devastating effect on the ecosystem.