Using Opera Mini seems to disable this "feature". Of course, doing so means all of my web traffic goes via Oslo. And of course, any apps using an http API are presumably affected too. I'm rather disappointed to hear about this.
Opera Mini uses its own protocol to talk to the proxy. HTTP is quite chatty, so there's a lot of mileage in reducing the headers by simply omitting a lot of unneeded information and compressing the rest.
