iPhone iCloud activation help.

I bought a used iPhone 4s off of Ebay and it just arrived a couple days ago. When I tried to activate it. it was locked on the old users account. I tried contacting them but they must of deleted their account because I cant find them at all. So I have this useless iPhone thats locked on someone else's account and I cant contact the person at all. I cant sell it either because its locked on someones account and the person I sell it to wont be able to activate it. Is there a way I can remove their account or something?