Problem with display of UIToolbar as a UIBarButtonItem in a modal view.

Question

I have a UIViewController that has a UIToolbar as the navigation bars right UIBarButtonItem. When in fullscreen as you can see on the top of the image, the toolbar displays correctly. However, when I present the same view controller modally (formSheet in this case) the toolbar doesn't display correctly.

The code I'm using for the bar is:

UIToolbar* toolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, toolbarWidth, 44)];

Where toolbarWidth is calculated with sizeWithFont:.

Can anybody tell me how I can fix this? I'm kind of confused.