[spectre]

I'm surprised the Maori Advisory Board of the Intellectual Property Office hasn't blocked this on the grounds that 'koha' is a Te Reo Maori word (translated as gift or offering). They tend to be highly protective of the language as it's considered to be taonga (treasure).

[metel]

I'd be surprised if it turned out they had any say in the matter. Imagine if the proud and venerable Brî'tíšh people had the power to block the usage of such words as "Windows" to describe a software product.

[aptwebapps]

Usage is one thing, trademark is another. And what pertains in the British Isles does necessarily pertain in New Zealand.