[FreezingKeeper]

They do [0]. You can also do it in their app if you are on a contract and therefore over 18 by definition.

[0] http://ask3.three.co.uk/srvs/cgi-bin/webisapi.dll/,/?new,kb=...

[Wildgoose]

In my experience that never worked. I eventually gave up trying to use them.

[gpderetta]

You can do through their app. But it is almost always broken. It took me months before I managed to get the app not to give me a 'temporary error'.