sbiddle: Green is the standard colour for all Chorus infrastructure.
Orange is only used for power and would never be used for telecommunications infrastructure by any telco.
I had an interesting conversation with someone online about this recently.
Although it is the norm, it is not the case in Christchurch and what appears to be some north island locations now.
Huaweii are providing the ducting for UFB here to Enable (Contracting Chorus), and it is infact Red/ red-Orange. (not to be confused with orange-orange :) ) as seen by the pic on their main site. http://www.enable.net.nz/
Installed in both Halswell, Bishopdale and now Rolleston. In some cases it is put into their thicker green pipe casings (not ducting) for a bit of protection. Terminated at a hub box, And then when it goes to the home, I believe it is the normal 20mm? green buried ducting with a couple of pairs inside.