I've programmatically created a UITabBarController that is loaded in my App Delegate like this:

- (void)applicationDidFinishLaunching:(UIApplication *)application {    
tabBarController = [[UITabBarController alloc] init];

myTableViewController = [[MyTableViewController alloc] init];
UINavigationController *tableNavController = [[[UINavigationController alloc] initWithRootViewController:myTableViewController] autorelease];
myTableViewController.title = @"Tab 1";
[myTableViewController release];

mySecondTableViewController = [[MySecondTableViewController alloc] init];
UINavigationController *table2NavController = [[[UINavigationController alloc] initWithRootViewController:mySecondTableViewController] autorelease];
mySecondTableViewController.title = @"Tab 2";
[mySecondTableViewController release];

tabBarController.viewControllers = [NSArray arrayWithObjects:tableNavController, table2NavController, nil]; 

[window addSubview:tabBarController.view];
[window makeKeyAndVisible];
}

Now the issue I have is that I can get into the views no problem, but when I try and click onto any item in the Table View, I can't get a secondary table view to appear in any tab. The tabs work absolutely fine, just the secondary views. I'm using the code below in my myTableViewController to run when selecting a specific row (the code reaches the HELP line, and crashes)...

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
NSUInteger row = [indexPath row];
    // this gets the correct view controller from a list of controllers
SecondaryViewController *svc = [self.controllers objectAtIndex:row];

    /*** HELP NEEDED WITH THIS LINE ***/    
[self.navigationController pushViewController:svc animated:YES];

}

Simply put, I'm trying to switch views to the new view controller whilst keeping the tabs available and using the navigation to go back and forth (like in the iTunes App).

Any help appreciated.

Thanks