Hey there, I just upgraded to the S2 a few days ago and noticed the wi-fi has many problems, one being that it works for about 5mins then stops, at this point I have to restart my phone and it starts working for a little while again. Problem 2 is its very weak signal unless you're sitting directly next to the router. The app "wifi fixer" seems to have done the trick somewhat but how do I fix this problem via the phones settings? Is it a proxy problem? I called up o2 and they said it could be my router.