For once, I'm NOT going to pick on the website, and I haven't even had my second cup of coffee yet!
But, since we are now into real trivial matters, let me just say this is IMO a FEATURE, not a bug. I have always liked the auto advance from box to box.
Takes longer to open up a file and cut and paste than to type 3 groups of 3 numbers, but then again, I know my AE # better than my phone number.