Iso c++ forbids declareation of uipopovercontroller

I want to update my game to ios4
so I download openfeint 2.51 and do everything readme said

but when I built, I got 115 errors

all about iso c++ forbids declareation of uipopovercontroller with no type

please help

when I use device-3.0,it’s ok
but with device-4.0,115 errors :shock: