Flipped UIViewController not getting released?

[sorted-bits]

I am flipping a UIViewController from another UIViewController, once a button is pressed, like this:

SomeViewController* someViewController = [[SomeViewController alloc] init];

[self flipToViewController: someViewController fromView:_myButton asChildWithSize:CGRectInset(self.view.frame, 50, 50).size withCompletion:^{
}];

In my flipped UIViewController I have a button which triggers the following method:

[self dismissFlipWithCompletion:NULL];

Just like in the example. The thing is, my UIViewController is observing an object and on dealloc I remove the observers. But my UIViewController is never released.

If I exchange the flip transition for a 'normal' addSubview action. The view is nicely released once I removeFromSuperView the view of the UIViewController.

SomeViewController* someViewController = [[SomeViewController alloc] init];
[self.views addSubView:someViewController.view];

[vimer]

same problem, please someone fix it