hmm do ya know what's wrong with your sunrise shots? :think:
i suspect you're using centre-weighted metering or matrix metering (the canon equivalent) that takes the whole scene in consider. try using spot metering on the sun to expose that properly, instead of the camera trying to get everything decently exposed which leaves the sun as a burned detail.
what i usually do, is go into M mode, shoot, review, and tweak shutterspeed and aperture to over or under accordingly.
rememeber that the 'correct' exposure is just what the camera calculates. most of the beautiful sunrise/sunset shots are intentionally underexposed (or even overexposed maybe) to fulfil the photog's vision of what he sees.