It's been on Trademe and they pulled it because it has a UK charger and power adaptor but is back up without mention of those pieces. Hopefully it is left alone now. If they pull it again the advertisement will stay here but thought I might as well see if anyone here is interested in it now.

http://www.trademe.co.nz/Browse/Listing.aspx?id=488670704

From TM description:
This is my Galaxy S2, which has been used on Telecom XT for the last year or so. It is fully unlocked and has been updated to the latest v4.0.3 android version. 

Included in the auction is also my desktop dock, which has light wear from the daily use it has had. 

As well as this, the phone has the genuine Samsung extended battery pack in/on it. The original smaller battery and cover are included. 

There will be a 16GB microSD card supplied to ensure the new owner can make the most of the multimedia abilities of the phone too. 

It has lived its life with an Invisible Shield cover on it but this has been removed for the auction due to it not looking very nice any more. I will supply the remaining covers for the new owner to install as they see fit. 

The auction includes the following: 
1x Samsung Galaxy S2 
1x Micro USB Cable 
1x Micro USB charger 
1x Original battery and back case 
1x Samsung Extended battery and back case (2000mAh) 
1x Samsung Desktop dock 
1x 16GB MicroSD card 
2x Front unused Invisible Shield covering 
1x Back unused Invisible Shield covering 
1x Bottom unused Invisible Shield covering 
1x Invisible Shield application tools

In the interest of full disclosure there are two minor cosmetic problems with this phone. One is that there is a small hairline scratch on the left hand side of the screen. It's not deep enough to feel and you can't see it when the screen is on so it's never been an issue for me. Second is a small abrasion on the top right side of the main body. It's not deep and you only know it's there when you look for it.