Automatic Trans Problem?

Hey every1. Me and my friend were having a talk about cars, and he said his car is having trouble switching from 1st to 2nd gear ( its automatic ). I took a ride in it, and noticed the problem. It will switch out of 1st, just in a jerky wired way when around 4K revs. Like it sounds like it over revs, but it doesnt.. I know nothing about automatics, any1 no the problem?