Option dialog on iPad bad visualization, double

Creating a list bigger than ipad mini screen's height, looks like is fine but when i scroll down i can see two list, one static and other that can be scrolled. When clicking i'm selecting in "scrollable" list. Screenshot: http://img836.imageshack.us/img836/6460/v78n.png

var lst = Titanium.UI.createOptionDialog ({
    title  : params.txt,
    options: params.options,
    cancel : -1
}).show();

Thanks