The battery life on this phone is pretty amazing, the 2,600mAh battery does work well.
I guess your problem can be with the network reception.
If you use 3G and aren't getting proper signals, the phone strives hard to search for a better signal, and hence in that case, that keeps the processor awake, and it leads in the mre consumption of battery than usual.
I would recommend you to switch to 2G mode, or Wi-Fi if possible. And then observe for sometime. If ever your problem isn't solved after trying what I wrote above, try uninstalling any 3rd party apps that you think are useless, (Not 100% sure about this, because Android does manage it's apps well, and there are very less chances of battery drain through an app) or you can then try to let the HTC Service guys know your issue, and I hope they do something for you.
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, I would be glad to help you out.
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