Just a short post about a fairly obscure problem migrating from iPhone v 1 directly to iPhone v 4.
iPhone version 1 did not support Multimedia Message Service (MMS) only Short Message Service (SMS or Text only messaging). I received an iPhone v 4 for a Christmas present, that meant I was going from iPhone v1 to v4. Purchased the phone at an Apple store and made the necessary ATT account changes while there. Thought everything was fine.
Came home eager to try all the features of the new phone, but, MMS did not work. Interesting, Chris, my spousal equivalent, owns an iPhone 3 GS, he couldn't send MMS either. Naturally, I thought there must be a network problem, he has never had a problem before with MMS.