Replying to Serious question involving ergonomics of keypads....

I'm just back from a skiing trip to italy and we had a heated argument at the bar that was sparked by the following problem:

Why are the numbers on a computer/calculator keypad listed like:

789

456

123

and on a cellphone the other way around?

like this:

123

456

789

NSers, i turn to your united intellect to answer this question for me!

thanks in advance!

Serious/good answers will be rewarded with +k and maybe even other goodies !

-Fred