I am having exactly the same problem, I am on Optus in Australia. This always worked with 2.0 but although 2.0.1 installed correctly now carrier update fails.
me too, just got an iphone at softbank today. software 2.01 and get a dialog asking to update the carrier's info, click ok then get the error 0xE8000001
Same problem here in New Zealand. New iPhone 3g with Vodafone. Just updated it to 2.0.1 and now I get the "unable to carrier settings" error every time I sync. It tells me that there are carrier updates available I click install and then I get the error.