I see. They probably hard-coded the TX power limitation for EU countries in the SoC-specific flash partition, so the firmware adapts its functionality to this limit.
A very bad idea those times, since OEMs won't be able to sell those devices to foreign customers.
Me thinks, it could be another regulation crap required from manufacturers by the EU bureaucrats in order to be able to sell gear in the EU. Too bad, but seems you have to buy an US model to get 27 dBm. I'm living in Europe, but I also bought US versions of certain technical stuff b/c of stupid EU regulations. Not that I use 27 dBm here in Germany, but I hate being ruled like a child when buying e.g. an iPod with volume regulations for EU kids. That's the famous "global market".