i upgraded to the 2.2 software about 4 days ago and since then, my phone has been acting out, with the screen pausing during use or flickering when i try to scrolll through my home screens. today, i had my phone off for half the day and turned it on. all i'm getting is a white screen with flickering vertical lines on the right side. so far the iphone's been good, ever since i replaced it 3 times in the beginning due to build quality and screen defects. i'm stuck with a non-functioning iphone and i was supposed to be on call for work tonight. just my luck? anyhow, would it be possible to exchange this at the apple store even though it's been 5 months since purchase?