Sorry, didn't notice that.
I guess you just have to get used to it. Find another position for your arm (or the guitar), it seems like you're not holding it the right way. It shouldn't be uncomfortable playing an acoustic guitar. Do you sit or stand when you play?
There are some guitars though with a round molded plastic back that might be more comfortable. At least Yamaha have put out some models. I just hate the sound of those. Too plastic (surprise, surprise).
My acoustic has a Jumbo body. I guess that would be even worse for you though.
I tried a a couple of Blueridge acoustics the other week in a music shop. The models I tested seemed to have had slightly smaller bodies that normally and sounded really nice. Here's their list of guitars (first of five pages):
http://www.sagamusic.com/catalog/pro...ID=2&BrandID=5
Check out those.