FBConnect in iphone 4.0 version is displayed as in browser

I developed an App with FBConnect using new Facebook SDK. It worked fine in 3.0 devices/simulators. But as the code is executed in 4.0, the fbconnect page is displayed as in browser i.e showing addressbar at the top, some controls in t开发者_StackOverflow中文版he bottom.. what the problem

Find the method

- (void)authorizeWithFBAppAuth:(BOOL)tryFBAppAuth
                    safariAuth:(BOOL)trySafariAuth 

and pass both parameters as NO