The stock messaging app has a bug that causes it to treat pics as videos *if* the msg also contains text (it works fine if there's no text in the msg). The problem is on the receive side, not sending (I saw this behavior no matter what phone or OS the message was sent from). This problem predates JB, and is one of the reasons I gave up on the stock messaging app and switched to GO SMS Pro. I'm glad I did, third party msg apps offer many benefits over the plain vanilla stock app. Try GO SMS Pro, Handcent, or any of the other popular third party apps, you won't go back.