I finally figured it out... I was initializing the FBSession inside my app delegate s applicationDidFinishLaunching method. I then triggered the Facebook login code in my view controller s viewDidAppear.

However, applicationDidFinishLaunching looked like this:

- (void)applicationDidFinishLaunching:(UIApplication *)application {    
    [window addSubview:viewController.view];
    [window makeKeyAndVisible];

    self.session = [FBSession sessionForApplication:FB_API_KEY secret:FB_APP_SECRET delegate:self];
}

This means that I was showing the window before I was initializing the FBSession, and apparently a nil session leads to the behavior I described above. After changing applicationDidFinishLaunching to create the FBSession first, everything now works as expected. Doh... ;)

Thanks Mirko, I had the exact same problem but reached via a different implementation. Here are the facts:

• The problem was the same on the simulator and on a physical device. The wrong user agent is a red herring.
• Before displaying the dialog (either directly via FBLoginDialog or using the FBLoginButton), you must have established your session (either via "[[FBSession sessionForApplication:kApiKey secret:kApiSecret delegate:self] retain];" or the proxy method). Or calling [session resume] on an already existing session.
• The state of the session object before displaying the dialog has no effect. As long as I have called the above methods to establish my session, I can do "session = nil" or "[session logout]", and I still get the correct dialog. If I do not establish my session first, I get the wrong full homepage effect.

I haven t worked with the FaceBook API library, but did you try changing dialog.frame before sending the show message?

Have you tried this on a device? What OS are you building against? I m using an almost identical call with no problems (-init, vs. initWithSession). Also, I m assuming you have a window and view architecture already set up behind this, correct?

I only had this problem, only the device, not on the simulator. Apparently the Facebook page is using the device s user agent to render the correct page. If you wanted to, you should be able to change that by adding a User Agent header to the http calls FB Connect s Web View is making.

I just pulled up my code and saw that I wrote a workaround for the same problem. Basically the issue is Facebook connect wants you to put a FBLoginButton in your app, which then opens up the Login Dialog. In order to display the dialog without the button I did this:

faceBookSession = [FBSession sessionForApplication:kFacebookAPIKey secret:kFaceBookAPISeceret delegate:self];
    if (![faceBookSession resume]) {
        FBLoginButton *button = [[FBLoginButton alloc] init];
        [button performSelector:@selector(touchUpInside)];
        [button release];
    }