iPad application with multiple DetailView and have navigation in detailview

i search for a way to have multiple detail view in iPad application and i find the sample code in apple developer site http://developer.apple.com/library/ios/#samplecode/MultipleDetailViews/Introduction/Intro.html , but now i want to have navigation in detail view which this sample does not cover, i add uinavigationcontroller to detail view as :

-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
 {
     ReportsViewController_iPad *master = [[ReportsViewController_iPad alloc] initWithNibName:@"ReportsViewController_iPad" bundle:nil];
 
     DetailViewController_iPad *detail = [[DetailViewController_iPad alloc] initWithNibName:@"DetailViewController_iPad" bundle:nil];
 
     UINavigationController *masterNavController = [[[UINavigationController alloc] initWithRootViewController:master ] autorelease];
 
     UINavigationController *detailNavController = [[[UINavigationController alloc] initWithRootViewController:detail ] autorelease];
 
     splitViewController.viewControllers = [NSArray arrayWithObjects:masterNavController , detailNavController, nil];
 
     [window addSubview:splitViewController.view];
     [window makeKeyAndVisible];
 
     return YES;
 }
 

but when i run the sample i got error

[UINavigationController showRootPopoverButtonItem:]: unrecognized selector sent to instance...

showRootPopoverButtonItem is a method define in a protocol in RootViewController

@protocol SubstitutableDetailViewController
- (void)showRootPopoverButtonItem:(UIBarButtonItem *)barButtonItem;
- (void)invalidateRootPopoverButtonItem:(UIBarButtonItem *)barButtonItem;
@end

So Thanks inadvance

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