Is FBconnect from 2010 out of use?

Is FBconnect from 2010 out of use?

I have taken over an app project for iOS 5 that was built in 2010/2011.
The project has facebook connectivity but it does not work and I suspect
it is because it uses an old interface towards fb. In the files I can see
that the FBConnect.h file is Copyright 2010.
Is there any legacy support or do I have to throw this out and use a newer
interface instead?
In my code I have among other things
#define ACCESS_TOKEN_KEY @ ######
#define EXPIRATION_DATE_KEY @
if ([defaults objectForKey:ACCESS_TOKEN_KEY] && [defaults
objectForKey:EXPIRATION_DATE_KEY]) {
facebook.accessToken = [defaults objectForKey:ACCESS_TOKEN_KEY];
facebook.expirationDate = [defaults
objectForKey:EXPIRATION_DATE_KEY];
}
From what I can see on the fb API it wants an App ID and a Secret instead
of the above.
When running, it doesn't crash but neither is it able to connect to fb.
The login screen does not show and it seems always to end up in the
- (void)fbDidNotLogin:(BOOL)cancelled {
[[self delegate] didNotLoginOnFacebook:(BOOL)cancelled];
}
The app is built for iOS5 and forward. I know that iOS6 has built in
facebook integration which would probably make everything easier. Question
now is if my code is useable at all or if I have to throw it out?