The one thing keeping the HTC Diamond from sweeping across America as the next big competitor (and a capable one at that) to the iPhone 3G is the HTC Diamond’s lack of support for the 850Mhz GSM frequency band that us Yankees love to use. Sure, 850Mhz has better penetrating power than the higher frequency 
900Mhz band that’s used in ubiquity throughout the rest of the world, but it still means the US has to wait for European handsets to make the jump to the US.
But, the thing is, Euro handsets usually lag in hitting the US market due hardware limitations. We were under the impression that the HTC Diamond, in European trim, lacked the radio hardware to jump on the 850Mhz frequency in the US. Lo and behold, there’s 850Mhz support built-in to the HTC Diamond! Who knew?
A new cellular radio ROM has surfaced at XDA developers that somehow (we’re betting there’s some magic involved here) enables 850Mhz support in the HTC Diamond. This basically means an HTC Diamond with this radio ROM is now a US-compatible, quad-band GSM smartphone – albeit, EDGE data is about as good as it’s going to get.
So, if you just can’t wait to jump on the HTC Diamond before it hits the US in official quad-band spec, grab a European HTC Diamond and give it some unofficial ROM-love. Just remember, you’re messing around with critical firmware at your own risk.
[Via: xda]